Ews Class

Provides properties and methods for working with e-mails on MS Exchange server via Exchange Web Services.

Inheritance Hierarchy

SystemObject
MailBee.EwsMailEws

Namespace: MailBee.EwsMail
Assembly: MailBee.NET (in MailBee.NET.dll) Version: 12.5.0 build 687 for .NET 4.5

Syntax

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public class Ews : IComponent, IDisposable

Public Class Ews
	Implements IComponent, IDisposable

The Ews type exposes the following members.

Constructors

	Name	Description
	Ews	Creates an instance of Ews class.
	Ews(String)	Creates and unlocks an instance of Ews class.

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Methods

	Name	Description
	AddAttachmentToItem	Adds an attachment to an existing item.
	AddAttachmentToItemAsync	Async/await version of AddAttachmentToItem(ItemId, String, String).
	Autodiscover	Automatically determines the URL of the EWS server.
	CopyItem	Copies the specified item (e.g. mail message) into the specified folder.
	CopyItemAsync	Async/await version of CopyItem(ItemId, FolderId).
	CreateFolder	Creates a folder in the MS Exchange account.
	CreateFolderAsync	Async/await version of CreateFolder(String, FolderId).
	CreatePropSet	Creates EWS Managed API PropertySet object.
	DeleteAttachment	Deletes the attachment with the specified filename from the specified item.
	DeleteAttachmentAsync	Async/await version of DeleteAttachment(ItemId, String, Boolean, Boolean).
	DeleteAttachments	Deletes all attachments in the specified item.
	DeleteAttachmentsAsync	Async/await version of DeleteAttachments(ItemId).
	DeleteFolder	Deletes a folder with the specified ID.
	DeleteFolderAsync	Async/await version of DeleteFolder(FolderId).
	DeleteItem	Deletes the specified item (e.g. mail message).
	DeleteItemAsync	Async/await version of DeleteItem(ItemId).
	DeleteItems	Deletes the specified item (e.g. mail message).
	DeleteItemsAsync	Async/await version of DeleteItems(IEnumerableItemId).
	Dispose	Closes all opened network connections (if any) and releases any used system resources.
	Dispose(Boolean)	When overridden in a derived class, must release unmanaged and optionally managed resources used by the component.
	DownloadEntireMessage	Downloads the specified item by its ID and returns it as MailMessage object.
	DownloadEntireMessageAsync	Async/await version of DownloadEntireMessage(ItemId).
	DownloadFolderByFullName(String)	Gets the reference to the folder denoted by its full name in the MS Exchange account.
	DownloadFolderByFullName(FolderId, String)	Gets the reference to the given folder in the specified containing folder in the MS Exchange account.
	DownloadFolderByFullName(String, Int32)	Gets the reference to the folder denoted by its full name in the MS Exchange account.
	DownloadFolderByFullNameAsync(String)	Async/await version of DownloadFolderByFullName(String).
	DownloadFolderByFullNameAsync(FolderId, String)	Async/await version of DownloadFolderByFullName(FolderId, String).
	DownloadFolderByFullNameAsync(String, Int32)	Async/await version of DownloadFolderByFullName(String, Int32).
	DownloadFolderById(FolderId)	Gets the reference to the folder with given ID in the MS Exchange account.
	DownloadFolderById(FolderId, PropertySet)	Gets the reference to the folder with given ID in the MS Exchange account, also requesting the specified properties.
	DownloadFolderByIdAsync(FolderId)	Async/await version of DownloadFolderById(FolderId).
	DownloadFolderByIdAsync(FolderId, PropertySet)	Async/await version of DownloadFolderById(FolderId, PropertySet).
	DownloadFolderByShortName	Gets the reference to the given folder in the MS Exchange account.
	DownloadFolderByShortNameAsync	Async/await version of DownloadFolderByShortName(FolderId, String).
	DownloadFolders(Boolean)	Downloads the list of folders of the MS Exchange account.
	DownloadFolders(FolderId, Boolean, Boolean)	Downloads the list of folders of the MS Exchange account.
	DownloadFolders(FolderId, FolderView, SearchFilter, Boolean)	Downloads the list of folders of the MS Exchange account.
	DownloadFoldersAsync(Boolean)	Async/await version of DownloadFolders(Boolean).
	DownloadFoldersAsync(FolderId, Boolean, Boolean)	Async/await version of DownloadFolders(FolderId, Boolean, Boolean).
	DownloadFoldersAsync(FolderId, FolderView, SearchFilter, Boolean)	Async/await version of DownloadFolders(FolderId, FolderView, SearchFilter, Boolean).
	DownloadItem(FolderId, Int32)	Downloads an item in the specified folder at the specified index.
	DownloadItem(ItemId, EwsItemParts)	Downloads the specified portions of the specified item by its ID.
	DownloadItem(ItemId, PropertySet)	Downloads the specified item by its ID using PropertySet settings.
	DownloadItem(FolderId, Int32, EwsItemParts)	Downloads the specified portions of an Exchange item in the specified folder at the specified index.
	DownloadItem(FolderId, Int32, PropertySet)	Downloads an item in the specified folder at the specified index using PropertySet settings.
	DownloadItemAsync(FolderId, Int32)	Async/await version of DownloadItem(FolderId, Int32).
	DownloadItemAsync(ItemId, EwsItemParts)	Async/await version of DownloadItem(ItemId, EwsItemParts).
	DownloadItemAsync(ItemId, PropertySet)	Async/await version of DownloadItem(ItemId, PropertySet).
	DownloadItemAsync(FolderId, Int32, EwsItemParts)	Async/await version of DownloadItem(FolderId, Int32, EwsItemParts).
	DownloadItemAsync(FolderId, Int32, PropertySet)	Async/await version of DownloadItem(FolderId, Int32, PropertySet).
	DownloadItemIds(FolderId, Boolean)	Downloads IDs of all or unread items in the specified folder.
	DownloadItemIds(FolderId, ItemView, Boolean)	Downloads IDs of items in the specified folder in the specified ItemView range.
	DownloadItemIdsAsync(FolderId, Boolean)	Async/await version of DownloadItemIds(FolderId, Boolean).
	DownloadItemIdsAsync(FolderId, ItemView, Boolean)	Async/await version of DownloadItemIds(FolderId, ItemView, Boolean).
	DownloadItems(FolderId, Boolean)	Downloads all or unread items in the specified folder.
	DownloadItems(IEnumerableEwsItem, EwsItemParts)	Downloads the specified portions of the specified items.
	DownloadItems(IEnumerableEwsItem, PropertySet)	Downloads the specified items using PropertySet settings.
	DownloadItems(FolderId, ItemView, Boolean)	Downloads items in the specified folder in the specified ItemView range.
	DownloadItems(FolderId, ItemView, Boolean, EwsItemParts)	Downloads the specified portions of the items in the specified ItemView range in the specified folder.
	DownloadItems(FolderId, ItemView, Boolean, PropertySet)	Downloads items in the specified folder in the specified ItemView range using PropertySet settings.
	DownloadItems(FolderId, Int32, Int32, Boolean)	Downloads items in the specified folder in the specified range.
	DownloadItems(FolderId, Int32, Int32, Boolean, EwsItemParts)	Downloads the specified portions of Exchange items in the specified folder in the specified range.
	DownloadItems(FolderId, Int32, Int32, Boolean, PropertySet)	Downloads items in the specified folder in the specified range using PropertySet settings.
	DownloadItemsAsync(FolderId, Boolean)	Async/await version of DownloadItems(FolderId, Boolean).
	DownloadItemsAsync(IEnumerableEwsItem, EwsItemParts)	Async/await version of DownloadItems(IEnumerableEwsItem, EwsItemParts).
	DownloadItemsAsync(IEnumerableEwsItem, PropertySet)	Async/await version of DownloadItems(IEnumerableEwsItem, PropertySet).
	DownloadItemsAsync(FolderId, ItemView, Boolean)	Async/await version of DownloadItems(FolderId, ItemView, Boolean).
	DownloadItemsAsync(FolderId, ItemView, Boolean, EwsItemParts)	Async/await version of DownloadItems(FolderId, ItemView, Boolean, EwsItemParts).
	DownloadItemsAsync(FolderId, ItemView, Boolean, PropertySet)	Async/await version of DownloadItems(FolderId, ItemView, Boolean, PropertySet).
	DownloadItemsAsync(FolderId, Int32, Int32, Boolean)	Async/await version of DownloadItems(FolderId, Int32, Int32, Boolean).
	DownloadItemsAsync(FolderId, Int32, Int32, Boolean, EwsItemParts)	Async/await version of DownloadItems(FolderId, Int32, Int32, Boolean, EwsItemParts).
	DownloadItemsAsync(FolderId, Int32, Int32, Boolean, PropertySet)	Async/await version of DownloadItems(FolderId, Int32, Int32, Boolean, PropertySet).
	DownloadNativeAttachments	Downloads attachments with the specified string IDs.
	DownloadNativeAttachmentsAsync	Async/await version of DownloadNativeAttachments(String, Boolean).
	EmptyFolder	Empties a folder with the specified ID.
	EmptyFolderAsync	Async/await version of EmptyFolder(FolderId, Boolean).
	Equals	Determines whether the specified object is equal to the current object. (Inherited from Object.)
	EwsItemsToItemIds	Creates the list of ItemId objects from the collection of EwsItem objects.
	Finalize	Allows an object to try to free resources and perform other cleanup operations before it is reclaimed by garbage collection. (Inherited from Object.)
	FindFolderIdByFullName(String)	Gets the ID of the folder denoted by its full name in the MS Exchange account.
	FindFolderIdByFullName(FolderId, String)	Gets the ID of the given folder in the specified containing folder in the MS Exchange account.
	FindFolderIdByFullName(String, Int32)	Gets the ID of the given folder in the MS Exchange account.
	FindFolderIdByFullNameAsync(String)	Async/await version of FindFolderIdByFullName(String).
	FindFolderIdByFullNameAsync(FolderId, String)	Async/await version of FindFolderIdByFullName(FolderId, String).
	FindFolderIdByFullNameAsync(String, Int32)	Async/await version of FindFolderIdByFullName(String, Int32).
	FindFolderIdByShortName	Gets the ID of the given folder in the MS Exchange account.
	FindFolderIdByShortNameAsync	Async/await version of FindFolderIdByShortName(FolderId, String).
	FolderExists(String)	Checks if the folder with the specified full name exists in the MS Exchange account.
	FolderExists(FolderId, String)	Checks if the given folder in the specified containing folder exists in the MS Exchange account.
	FolderExistsAsync(String)	Async/await version of FolderExists(String).
	FolderExistsAsync(FolderId, String)	Async/await version of FolderExists(FolderId, String).
	GetErrorDescription	Returns a textual description of the last occurred error.
	GetExchangeVersionString	Gets the MS Exchange version as a string.
	GetFolderByName	Finds the EwsFolder in the given list by the folder's full name.
	GetFolderView	Gets FolderView instance tuned for listing all the folders in the account.
	GetHashCode	Serves as the default hash function. (Inherited from Object.)
	GetType	Gets the Type of the current instance. (Inherited from Object.)
	InitEwsClient	Sets the default MS Exchange version.
	InitEwsClient(ExchangeVersion)	Sets the specific MS Exchange version.
	InitEwsClient(ExchangeVersion, TimeZoneInfo)	Sets the specific MS Exchange version.
	MemberwiseClone	Creates a shallow copy of the current Object. (Inherited from Object.)
	MoveFolder	Moves a folder into another folder.
	MoveFolderAsync	Async/await version of MoveFolder(FolderId, FolderId).
	MoveItem	Moves the specified item (e.g. mail message) into the specified folder.
	MoveItemAsync	Async/await version of MoveItem(ItemId, FolderId).
	OnErrorOccurred	Used by MailBee to raise ErrorOccurred event.
	OnLogNewEntry	Used by MailBee to raise LogNewEntry event.
	RenameFolder	Renames a folder in the MS Exchange account.
	RenameFolderAsync	Async/await version of RenameFolder(String, FolderId).
	RenameOrMoveFolder	Renames or moves a folder denoted by its full name rather than by ID.
	RenameOrMoveFolderAsync	Async/await version of RenameOrMoveFolder(String, String, ListEwsFolder).
	ResolveName	Resolves the specified name into e-mail addresses which exist on the given MS Exchange server.
	ResolveNameAsync	Async/await version of ResolveName(String).
	Search(FolderId, SearchFilter)	Searches the specified folder for items matching the given criteria.
	Search(FolderId, SearchFilter, ItemView)	Searches the specified folder for items matching the given criteria and delivers the results accordingly the specified ItemView.
	SearchAsync(FolderId, SearchFilter)	Async/await version of Search(FolderId, SearchFilter).
	SearchAsync(FolderId, SearchFilter, ItemView)	Async/await version of Search(FolderId, SearchFilter, ItemView).
	SendMessage	Sends MailBee mail message.
	SendMessageAndSaveCopy	Sends MailBee mail message and saves a copy in Sent Items or user-defined folder.
	SendMessageAndSaveCopyAsync	Async/await version of SendMessageAndSaveCopy(MailMessage, FolderId).
	SendMessageAsync	Async/await version of SendMessage(MailMessage).
	SetCredentials(ExchangeCredentials)	Sets the credentials (e.g. OAuth2) of the MS Exchange account for subsequent operations.
	SetCredentials(String, String)	Sets the login and password of the MS Exchange account for subsequent operations.
	SetServerUrl	Gets or sets the URL of EWS service on MS Exchange server.
	TestConnection	Makes a test connection to validate the current settings.
	TestConnectionAsync	Async/await version of TestConnection.
	ToString	Returns a string that represents the current object. (Inherited from Object.)
	UpdateItem	Writes the changes made to the item to the MS Exchange server.
	UpdateItemAsync	Async/await version of UpdateItem(EwsItem).
	UploadMessage(FolderId, MailMessage, Boolean)	Uploads MailBee's MailMessage into the specified folder on the MS Exchange server.
	UploadMessage(FolderId, Byte, Boolean)	Uploads raw message data into the specified folder on the MS Exchange server.
	UploadMessageAsync(FolderId, MailMessage, Boolean)	Async/await version of UploadMessage(FolderId, MailMessage, Boolean).
	UploadMessageAsync(FolderId, Byte, Boolean)	Async/await version of UploadMessage(FolderId, Byte, Boolean).

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Properties

	Name	Description
	CalculateFolderSizeOnDownload	Gets or sets if folder download operation must also calculate the folder size in bytes.
	DefaultFolderClass	Gets or sets the default class string to assign to folders being created.
	DeleteMethod	Gets or sets the mode of deleting items in EWS.
	EnableCompatibilityMode	Gets or sets if MailBee should work around bugs of Microsoft.Exchange.WebServices.dll library.
	EnableSslCertValidation	Gets or sets if SSL certificate of the server must be validated (in case of HTTPS connection).
	FolderLevelDelimiter	Gets or sets which character to use when delimiting nested folder names.
	LastResult	Gets a numeric code of the last error.
	Log	Gets the object used for logging MailBee activities into a file or memory buffer.
	MessageFoldersFilter	Gets SearchFilter instance for reducing the list of the downloaded folders to mail-specific folders.
	RequireHttps	Gets or sets if only HTTPS end points are allowed by auto-discover procedure.
	RootFolderType	Gets or sets the top of folder hierarchy in an MS Exchange account.
	Service	Gets a reference to the underlying ExchangeService object.
	Site	Gets or sets the object to be used as a site for the component.
	ThrowExceptions	Gets or sets whether the component will throw exceptions on errors.
	TrialDaysLeft	Gets the number of days left to the date of the trial license key expiration.
	Version	Gets the version of the MailBee assembly.

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Events

	Name	Description
	Disposed	Occurs after the component was disposed.
	ErrorOccurred	Occurs when the MailBeeException is thrown.
	LogNewEntry	Occurs when an entry is written into the log file (or into the memory buffer if Ews.Log.MemoryLog is true).

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Remarks

This class is a wrapper for a subset of EWS Managed API library functions. This wrapper lets the developer work with EWS items in the way typical for other MailBee components (for instance, native exceptions of EWS Managed API are wrapped with MailBeeException, logging with Log property, etc). However, Ews class still exposes native EWS Managed API objects and types so you can utilize EWS Managed API for advanced tasks not directly covered by MailBee.

Note
In .NET Core, EWS is supported starting from .NET Core 2.0 (async methods only). In UWP, EWS requires Windows 10 Fall Creators Update as Min Target (async methods only). In .NET Framework, EWS is supported starting from .NET Framework v3.5 (sync methods only, not async). See more details in EWS Managed API topic.

To use EWS, you need to add a reference to MailBee.NET.EWS.DLL (MailBee.NET.EWS package if you're using Nuget). In its turn, MailBee.NET.EWS.DLL references Managed EWS API (Microsoft.Exchange.WebServices.dll or Microsoft.Exchange.WebServices.NETStandard.dll in case of .NET Framework or .NET Core/UWP, respectively). The MailBee.NET.EWS package installs the dependent DLLs automatically.

The typical procedure of accessing EWS:

Create Ews instance.
Init Ews instance by requesting the minimum required MS Exchange server version (InitEwsClient(ExchangeVersion) or InitEwsClient() if any version will suffice for you).
Call Autodiscover(String) or SetServerUrl(String) to specify the server host (automatically or manually, respectively).
Set the user credentials with SetCredentials(String, String) method (or SetCredentials(ExchangeCredentials) for OAuth 2.0, such as for Office 365).
Now you can access e-mails, folders, etc.

Examples

This sample demonstrates various scenarios of interacting with MS Exchange server. That's what we do there:

Connect to the explicitly defined server host or auto-discover the server host from the e-mail address.
Send e-mail and save the copy in Sent Items.
Download folders (get folder list, message count in each folder and its size in bytes).
Search, sort and download messages and their parts in different ways.
Display message contents, save, add and delete attachments.
Set Unread message flag.
Manipulate folders (e.g. create).

Note
In .NET Core or UWP, replace sync methods with their async versions.

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using System;
using System.Collections.Generic;
using System.Linq;
using System.IO;
using MailBee.EwsMail;
using Microsoft.Exchange.WebServices.Data;

// We need this because MailMessage type exists in both MailBee and Managed EWS.
using MailBeeMailMessage = MailBee.Mime.MailMessage;
using MailBeeAttachment = MailBee.Mime.Attachment;

class Program
{
    // We use this for displaying all strings but IDs.
    static string Shorten(string text, int maxLen)
    {
        if (text == null || text.Length <= maxLen)
        {
            return text;
        }
        else
        {
            return text.Substring(0, maxLen - 2) + "..";
        }
    }

    // Because IDs usually have diff. endings but the same beginning, we'd better leave ending part.
    static string ShortenId(string text)
    {
        int maxLen = 10;
        if (text == null || text.Length <= maxLen)
        {
            return text;
        }
        else
        {
            return ".." + text.Substring((text.Length - maxLen) + 2);
        }
    }

    // Remove CRLFs from strings to make console outputs easier to read.
    static string Flatten(string text)
    {
        if (text == null)
        {
            return null;
        }
        else
        {
            return text.Replace("\r\n", " ").Replace('\n', ' ');
        }
    }

    static void Main(string[] args)
    {
        // If license key is not set in app.config or Registry, set it here.
        MailBee.Global.LicenseKey = "MN1XX-XXXXXXXX-XXXX";

        // Enable self-signed server certificates. Remove this line to connect only to well-established servers with valid certificates.
        Ews.EnableSslCertValidation = false;
        Ews ewsClient = new Ews();

        // Normally, use TimeZoneInfo.Local, or use TimeZoneInfo.Utc if getting "The specified time zone isn't valid" errors.
        ewsClient.InitEwsClient(ExchangeVersion.Exchange2010_SP1, TimeZoneInfo.Utc);
        // ewsClient.InitEwsClient(ExchangeVersion.Exchange2013_SP1, TimeZoneInfo.Utc); // If your Exchange server is newer or Office 365.

        // Log file can be used for debugging. You can also enable .NET Sockets own log by adding System.Net trace listener in app.config file (.NET Framework only).
        ewsClient.Log.Enabled = true;
        ewsClient.Log.Filename = @"C:\Temp\log.txt";
        ewsClient.Log.Clear();

        // Disabled Gzip results in more traffic (that's bad) but makes debugging easier ("network.log" file will contain human-readable data).
        ewsClient.Service.AcceptGzipEncoding = false;

        string email = "user@contoso.com"; // On-premise Exchange account
        // string email = "user@company.onmicrosoft.com"; // Microsoft account

        // Set on-premise Exchange server URL.
        ewsClient.SetServerUrl("http://domain/EWS/Exchange.asmx");
        ewsClient.SetCredentials(email, "secret");

        // Or set Office 365 server URL.
        // ewsClient.SetServerUrl("https://outlook.office365.com/EWS/Exchange.asmx");
        // ewsClient.SetCredentials(email, "secret"); // Login/password auth
        // ewsClient.SetCredentials(oAuth2Creds); // Or OAuth2 creds, obtained separately (oAuth2Creds must be of ExchangeCredentials type)

        // Or use autodiscover (must be configured on the Exchange server, Office 365 server has autodiscover working).
        // ewsClient.Autodiscover(email);
        // ewsClient.RequireHttps = true;
        // ewsClient.SetCredentials(email, "secret");

        // Send a mail message with attachment to myself.
        MailBeeMailMessage msg = new MailBeeMailMessage();
        msg.Subject = "Test from EWS";
        msg.BodyPlainText = "Test at " + DateTime.Now.ToString();
        msg.BodyHtmlText = "<html>Test at " + DateTime.Now.ToString() + "</html>";
        msg.Attachments.Add(@"C:\Temp\file.doc"); // Adjust this path to make it denote an existing file.
        msg.To.AddFromString("User <user@contoso.com>");
        msg.From.AsString = "User <user@contoso.com>";
        msg.SetUniqueMessageID(null);
        ewsClient.SendMessageAndSaveCopy(msg, null); // Also save copy to Sent Items.
        // ewsClient.SendMessage(msg); // Or just send.

        ewsClient.CalculateFolderSizeOnDownload = true;
        List<EwsFolder> folders = ewsClient.DownloadFolders(null, false, true);
        foreach (EwsFolder folder in folders)
        {
            Console.WriteLine(string.Format("Folder: '{0}', total msgs: {1}, unread: {2}, size in bytes: {3}",
                folder.ShortName, folder.TotalCount, folder.UnreadCount, folder.Size));
            Console.WriteLine(folder.FullName);
        }

        // Get Sent Items folder from its well-known ID.
        EwsFolder sentFolder = ewsClient.DownloadFolderById(WellKnownFolderName.SentItems);
        Console.WriteLine(string.Format("You have {0} sent messages(s)", sentFolder.TotalCount));
        EwsItemList sentItems = ewsClient.DownloadItems(sentFolder.Id, null, false, EwsItemParts.GenericItem);
        EwsItem lastSentItem = sentItems.FindLast(i => i.Subject == "Test from EWS");
        if (lastSentItem != null)
        {
            // Demonstrate deleting messages. It's safe to delete this message because it's a test message we just sent.
            ewsClient.DeleteItem(lastSentItem.Id);
            Console.WriteLine("Deleted saved copy of a message we sent above");
        }
        else
        {
            Console.WriteLine("For some reason, there was no saved copy of a message we sent above");
        }

        // Will demonstrate various methods of getting EWS folder ID which then can then be used with many methods and properties.
        FolderId foldId = null;

        // Method 1: Get FolderId from folder name.
        foldId = ewsClient.FindFolderIdByFullName("Inbox");

        // Method 2: Remember the fact we already have folder list downloaded, grab FolderId from there.
        // Note: this method is currently not working due to a bug in EWS Managed API.
        EwsFolder inbox = folders.Find(fold => (fold.Id.FolderName.HasValue && fold.Id.FolderName.Value == WellKnownFolderName.Inbox));
        if (inbox == null)
        {
            // You'll most probably end up here.
            Console.WriteLine("Well-known folders only supported in Exchange 2013 and higher");
            // You'll also need:
            // ewsClient.InitEwsClient(ExchangeVersion.Exchange2013_SP1, TimeZoneInfo.Utc);
            // ewsClient.EnableCompatibilityMode = false;
            // Update Microsoft.Exchange.WebServices.dll (current version v2.2 crashes when Well-known folder status if retrieved).

            // For the time being, fallback to searching by name.
            inbox = folders.Find(fold => (fold.FullName.ToUpper() == "INBOX"));
        }
        if (inbox == null)
        {
            Console.WriteLine("Couldn't find Inbox");
            return;
        }
        else
        {
            foldId = inbox.Id;
        }

        // Method 3: Or simply get it via WellKnownFolderName directly. Easiest method.
        foldId = WellKnownFolderName.Inbox;

        Console.WriteLine("Download unread messages, body/headers");

        // Default view means "return all items in the natural order".
        ItemView unreadView = null;

        // Or, modify the default view so that only 10 newest items are returned, newer first.
        int pageSize = 10;
        int page = 0;

        // We'll display items in pages.
        unreadView = new ItemView(pageSize, 0);
        unreadView.OrderBy.Add(EmailMessageSchema.DateTimeReceived, SortDirection.Descending);
        EwsItemList unreadItems = null;

        // Here we not using DownloadItems which accepts startIndex and count as we don't know in advance how many items we have.
        // Instead, we're relying on MoreAvailable property from EWS to determine if there are more items left.
        Console.WriteLine("Press Esc to skip downloading the next page of messages (if any).");
        Console.WriteLine();
        while (true)
        {
            unreadItems = ewsClient.DownloadItems(foldId, unreadView, false, EwsItemParts.GenericItem | EwsItemParts.MailMessageBody | EwsItemParts.MailMessageRecipients);
            if (unreadView != null)
            {
                Console.WriteLine(string.Format("Downloading up to {0} message(s) starting at offset {1} from total of {2}, {3} message(s) actually downloaded.",
                    pageSize, unreadView.Offset, unreadItems.TotalCount, unreadItems.Count));
            }
            foreach (EwsItem item in unreadItems)
            {
                Console.WriteLine(string.Format("UID: {0} Text: {1} HTML: {2}",
                    ShortenId(item.UniqueId), Flatten(Shorten(item.BodyPlainText, 40)), Flatten(Shorten(item.BodyHtmlText, 40))));
                Console.WriteLine();
            }
            Console.WriteLine();
            if (unreadItems.MoreAvailable)
            {
                if (Console.KeyAvailable && Console.ReadKey().Key == ConsoleKey.Escape)
                {
                    Console.WriteLine("Esc pressed, will skip downloading the remaining pages and proceed to other examples.");
                    break;
                }
                else
                {
                    Console.WriteLine("Will download the next page.");
                }
            }
            else
            {
                Console.WriteLine("The last page is done.");
                break;
            }
            unreadView.Offset = unreadItems.NextPageOffset;
        }

        Console.WriteLine();

        Console.WriteLine("Download unread messages, full messages with attachments");
        unreadItems = ewsClient.DownloadItems(unreadItems, EwsItemParts.MailMessageFull);
        for (int i = 0; i < unreadItems.Count; i++)
        {
            EwsItem item = unreadItems[i];
            Console.WriteLine(string.Format("ID {0} size: {1}, attachments count: {2}, attachments: {3}", Shorten(item.UniqueId, 10), item.Size,
                item.MailBeeMessage.Attachments.Count,
                string.Join(", ", item.MailBeeMessage.Attachments.Cast<MailBeeAttachment>().Select(a => Shorten(a.Filename, 20)))));

            // For last message, do additional processing.
            if (i == unreadItems.Count - 1)
            {
                if (item.MailBeeMessage.Attachments.Count > 0)
                {
                    // Save all attachments using MailBee.
                    item.MailBeeMessage.Attachments.SaveAll(@"C:\Temp", true);

                    // Save a particular attachment using MailBee.
                    item.MailBeeMessage.Attachments[0].SaveToFolder(@"C:\Temp", true);
                }

                if (item.NativeMessage.Attachments.Count > 0)
                {
                    // Demonstrate working with attachments directly via Managed EWS API.
                    Console.WriteLine("  Attachment ID to name:  " +
                        string.Join(", ", item.NativeMessage.Attachments.Select(a => ShortenId(a.Id) + ": " + Shorten(a.Name, 20))));
                    IEnumerable<FileAttachment> fileAttachs = item.NativeMessage.Attachments.OfType<FileAttachment>();
                    if (fileAttachs.Count() > 0)
                    {
                        Console.WriteLine("  File attachment IDs: " + string.Join(", ", fileAttachs.Select(fa => ShortenId(fa.Id))));
                        FileAttachment fileAttach = fileAttachs.First();
                        fileAttach.Load(Path.Combine(@"C:\Temp", fileAttach.Name)); // This will save attachment to disk.
                    }
                }

                // Add attachment to message and then delete it. This is a kind of action you can only do with EWS and not with POP3 or IMAP, for example
                // (you cannot alter existing messages in POP3/IMAP, only mark them with flags).
                Console.WriteLine(string.Format("Attachment count: {0}", item.NativeMessage.Attachments.Count));
                FileAttachment newAttach = ewsClient.AddAttachmentToItem(item.Id, @"C:\Temp\test.txt", "filename.txt");
                item.NativeItem.Load();
                Console.WriteLine(string.Format("Attachment count: {0}", item.NativeMessage.Attachments.Count));
                Console.WriteLine("Will delete attachment just added");
                int countAttachsDeleted = ewsClient.DeleteAttachment(item.Id, newAttach.Id, true, true);
                item.NativeItem.Load();
                Console.WriteLine(string.Format("Attachment ID: {0}, instances deleted: {1}", ShortenId(newAttach.Id), countAttachsDeleted));
                Console.WriteLine(string.Format("Attachment count: {0}", item.NativeMessage.Attachments.Count));

                bool deleteOtherAttachs = false; // Set to true to enable deletion of other attachments. Do this only in test accounts, not in your normal account!
                if (deleteOtherAttachs)
                {
                    Console.WriteLine("Will delete the remaining attachments, if any");
                    ewsClient.DeleteAttachments(item.Id);
                    item.NativeItem.Load();
                    Console.WriteLine(string.Format("Attachment count: {0}", item.NativeMessage.Attachments.Count));
                }
            }

        }
        Console.WriteLine();

        // Update message flags to mark last message in the folder as unread (just to make sure the search for unread messages below will find at least one message).
        if (inbox.TotalCount > 0)
        {
            EwsItem item = ewsClient.DownloadItem(foldId, 0, EwsItemParts.IdOnly);
            item.IsRead = true;
            ewsClient.UpdateItem(item);
        }

        // Clear keyboard buffer to avoid earlier Esc strokes alter the code flow below.
        while (Console.KeyAvailable)
        {
            Console.ReadKey();
        }

        Console.WriteLine("Search for unread messages via using SearchFilter");
        SearchFilter filt = null; // "No filter" means "Search all messages".
        filt = new SearchFilter.IsEqualTo(EmailMessageSchema.IsRead, false); // Modify filter to allow only unread messages.
        unreadItems = ewsClient.Search(foldId, filt);
        string unreadUids = string.Join(", ", unreadItems.Select(it => ShortenId(it.UniqueId)));
        Console.WriteLine("Unread IDs (you can then pass them to DownloadItems): " + unreadUids);
        Console.WriteLine();

        // Simply display all messages in the folder with paging. We know in advance how many items to display so we don't need MoreAvailable and custom ItemView.
        Console.WriteLine("Display all messages in the folder in paged manner");
        Console.WriteLine("Press Esc to skip downloading the next page of messages (if any).");
        Console.WriteLine();
        EwsItemList items = null;
        while (page * pageSize < inbox.TotalCount)
        {
            // You can replace EwsItemParts.GenericItem with EwsItemParts.MailMessageFull to download full messages (with body/attachments) instead of basic info.
            // If you do this replacement, item.MailBeeMessage will no longer be null.
            items = ewsClient.DownloadItems(foldId, page * pageSize, pageSize, true, EwsItemParts.GenericItem);
            foreach (EwsItem item in items)
            {
                if (item.MailBeeMessage == null)
                {
                    Console.WriteLine(string.Format("To: '{0}', From: '{1}', Subject: '{2}', IsRead: {3}, Size: {4}",
                        Shorten(item.To, 20), Shorten(item.From, 20), Shorten(item.Subject, 20), item.IsRead, item.Size));
                }
                else
                {
                    Console.WriteLine(string.Format("To: '{0}', From: '{1}', Subject: '{2}', IsRead: {3}, Size: {4}, MailBeeMessage.Size: {5}",
                        Shorten(item.To, 20), Shorten(item.From, 20), Shorten(item.Subject, 20), item.IsRead, item.Size, item.MailBeeMessage.Size));
                }
            }
            page++;
            Console.WriteLine("------------");
            if (Console.KeyAvailable && Console.ReadKey().Key == ConsoleKey.Escape)
            {
                Console.WriteLine("Esc pressed, will skip downloading the remaining pages and proceed to other examples.");
                break;
            }
        }

        // Demonstrate working with deeply nested folders. EWS Managed API itself can only work with one level, MailBee adds this functionality on top of EWS.
        if (!ewsClient.FolderExists("Inbox/2nd level/3rd level"))
        {
            // Create a deeply nested folder.
            ewsClient.CreateFolder("Inbox/2nd level/3rd level", null);
            Console.WriteLine("Created folder \"Inbox/2nd level/3rd level\"");
        }
    }
}

Imports System.Collections.Generic
Imports System.Linq
Imports System.IO
Imports MailBee.EwsMail
Imports Microsoft.Exchange.WebServices.Data

' We need this because MailMessage type exists in both MailBee and Managed EWS.
Imports MailBeeMailMessage = MailBee.Mime.MailMessage
Imports MailBeeAttachment = MailBee.Mime.Attachment

Class Program
    ' We use this for displaying all strings but IDs.
    Private Shared Function Shorten(text As String, maxLen As Integer) As String
        If text Is Nothing OrElse text.Length <= maxLen Then
            Return text
        Else
            Return text.Substring(0, maxLen - 2) & ".."
        End If
    End Function

    ' Because IDs usually have diff. endings but the same beginning, we'd better leave ending part.
    Private Shared Function ShortenId(text As String) As String
        Dim maxLen As Integer = 10
        If text Is Nothing OrElse text.Length <= maxLen Then
            Return text
        Else
            Return ".." & text.Substring((text.Length - maxLen) + 2)
        End If
    End Function

    ' Remove CRLFs from strings to make console outputs easier to read.
    Private Shared Function Flatten(text As String) As String
        If text Is Nothing Then
            Return Nothing
        Else
            Return text.Replace(vbCrLf, " ").Replace(vbLf, " ")
        End If
    End Function

    Shared Sub Main(args As String())
        ' If license key is not set in app.config or Registry, set it here.
        MailBee.Global.LicenseKey = "MN1XX-XXXXXXXX-XXXX"

        ' Enable self-signed server certificates. Remove this line to connect only to well-established servers with valid certificates.
        Ews.EnableSslCertValidation = False
        Dim ewsClient As New Ews()

        ' Normally, use TimeZoneInfo.Local, or use TimeZoneInfo.Utc if getting "The specified time zone isn't valid" errors.
        ewsClient.InitEwsClient(ExchangeVersion.Exchange2010_SP1, TimeZoneInfo.Utc)
        ' ewsClient.InitEwsClient(ExchangeVersion.Exchange2013_SP1, TimeZoneInfo.Utc); ' If your Exchange server is newer or Office 365.

        ' Log file can be used for debugging. You can also enable .NET Sockets own log by adding System.Net trace listener in app.config file (.NET Framework only).
        ewsClient.Log.Enabled = True
        ewsClient.Log.Filename = "C:\Temp\log.txt"
        ewsClient.Log.Clear()

        ' Disabled Gzip results in more traffic (that's bad) but makes debugging easier ("network.log" file will contain human-readable data).
        ewsClient.Service.AcceptGzipEncoding = False

        Dim email As String = "user@contoso.com" ' On-premise Exchange account
        ' Dim email As String = "user@company.onmicrosoft.com" ' Microsoft account

        ' Set on-premise Exchange server URL.
        ewsClient.SetServerUrl("http://domain/EWS/Exchange.asmx")
        ewsClient.SetCredentials(email, "secret")

        ' Or set Office 365 server URL.
        ' ewsClient.SetServerUrl("https://outlook.office365.com/EWS/Exchange.asmx")
        ' ewsClient.SetCredentials(email, "secret") ' Login/password auth
        ' ewsClient.SetCredentials(oAuth2Creds)     ' Or OAuth2 creds, obtained separately (oAuth2Creds must be of ExchangeCredentials type)

        ' Or use autodiscover (must be configured on the Exchange server, Office 365 server has autodiscover working).
        ' ewsClient.Autodiscover(email)
        ' ewsClient.RequireHttps = True
        ' ewsClient.SetCredentials(email, "secret")

        ' Send a mail message with attachment to myself.
        Dim msg As New MailBeeMailMessage()
        msg.Subject = "Test from EWS"
        msg.BodyPlainText = "Test at " & DateTime.Now.ToString()
        msg.BodyHtmlText = "<html>Test at " & DateTime.Now.ToString() & "</html>"
        msg.Attachments.Add("C:\Temp\file.doc") ' Adjust this path to make it denote an existing file.
        msg.To.AddFromString("User <user@contoso.com>")
        msg.From.AsString = "User <user@contoso.com>"
        msg.SetUniqueMessageID(Nothing)
        ewsClient.SendMessageAndSaveCopy(msg, Nothing) ' Also save copy to Sent Items.
        ' ewsClient.SendMessage(msg) ' Or just send.

        ewsClient.CalculateFolderSizeOnDownload = True
        Dim folders As List(Of EwsFolder) = ewsClient.DownloadFolders(Nothing, False, True)
        For Each folder As EwsFolder In folders
            Console.WriteLine(String.Format("Folder: '{0}', total msgs: {1}, unread: {2}, size in bytes: {3}",
                folder.ShortName, folder.TotalCount, folder.UnreadCount, folder.Size))
            Console.WriteLine(folder.FullName)
        Next

        ' Get Sent Items folder from its well-known ID.
        Dim sentFolder As EwsFolder = ewsClient.DownloadFolderById(WellKnownFolderName.SentItems)
        Console.WriteLine(String.Format("You have {0} sent messages(s)", sentFolder.TotalCount))
        Dim sentItems As EwsItemList = ewsClient.DownloadItems(sentFolder.Id, Nothing, False, EwsItemParts.GenericItem)
        Dim lastSentItem As EwsItem = sentItems.FindLast(Function(i) i.Subject = "Test from EWS")
        If lastSentItem IsNot Nothing Then
            ' Demonstrate deleting messages. It's safe to delete this message because it's a test message we just sent.
            ewsClient.DeleteItem(lastSentItem.Id)
            Console.WriteLine("Deleted saved copy of a message we sent above")
        Else
            Console.WriteLine("For some reason, there was no saved copy of a message we sent above")
        End If

        ' Will demonstrate various methods of getting EWS folder ID which then can then be used with many methods and properties.
        Dim foldId As FolderId = Nothing

        ' Method 1: Get FolderId from folder name.
        foldId = ewsClient.FindFolderIdByFullName("Inbox")

        ' Method 2: Remember the fact we already have folder list downloaded, grab FolderId from there.
        ' Note: this method is currently not working due to a bug in EWS Managed API.
        Dim inbox As EwsFolder = folders.Find(Function(fold) (fold.Id.FolderName.HasValue AndAlso fold.Id.FolderName.Value = WellKnownFolderName.Inbox))
        If inbox Is Nothing Then
            ' You'll most probably end up here.
            Console.WriteLine("Well-known folders only supported in Exchange 2013 and higher")
            ' You'll also need:
            ' ewsClient.InitEwsClient(ExchangeVersion.Exchange2013_SP1, TimeZoneInfo.Utc)
            ' ewsClient.EnableCompatibilityMode = False
            ' Update Microsoft.Exchange.WebServices.dll (current version v2.2 crashes when Well-known folder status if retrieved).

            ' For the time being, fallback to searching by name.
            inbox = folders.Find(Function(fold) (fold.FullName.ToUpper() = "INBOX"))
        End If
        If inbox Is Nothing Then
            Console.WriteLine("Couldn't find Inbox")
            Return
        Else
            foldId = inbox.Id
        End If

        ' Method 3: Or simply get it via WellKnownFolderName directly. Easiest method.
        foldId = WellKnownFolderName.Inbox

        Console.WriteLine("Download unread messages, body/headers")

        ' Default view means "return all items in the natural order".
        Dim unreadView As ItemView = Nothing

        ' Or, modify the default view so that only 10 newest items are returned, newer first.
        Dim pageSize As Integer = 10
        Dim page As Integer = 0

        ' We'll display items in pages.
        unreadView = New ItemView(pageSize, 0)
        unreadView.OrderBy.Add(EmailMessageSchema.DateTimeReceived, SortDirection.Descending)
        Dim unreadItems As EwsItemList = Nothing

        ' Here we not using DownloadItems which accepts startIndex and count as we don't know in advance how many items we have.
        ' Instead, we're relying on MoreAvailable property from EWS to determine if there are more items left.
        Console.WriteLine("Press Esc to skip downloading the next page of messages (if any).")
        Console.WriteLine()
        While True
            unreadItems = ewsClient.DownloadItems(foldId, unreadView, False, EwsItemParts.GenericItem Or EwsItemParts.MailMessageBody Or EwsItemParts.MailMessageRecipients)
            If unreadView IsNot Nothing Then
                Console.WriteLine(String.Format("Downloading up to {0} message(s) starting at offset {1} from total of {2}, {3} message(s) actually downloaded.",
                    pageSize, unreadView.Offset, unreadItems.TotalCount, unreadItems.Count))
            End If
            For Each item As EwsItem In unreadItems
                Console.WriteLine(String.Format("UID: {0} Text: {1} HTML: {2}",
                    ShortenId(item.UniqueId), Flatten(Shorten(item.BodyPlainText, 40)), Flatten(Shorten(item.BodyHtmlText, 40))))
                Console.WriteLine()
            Next
            Console.WriteLine()
            If unreadItems.MoreAvailable Then
                If Console.KeyAvailable AndAlso Console.ReadKey().Key = ConsoleKey.Escape Then
                    Console.WriteLine("Esc pressed, will skip downloading the remaining pages and proceed to other examples.")
                    Exit While
                Else
                    Console.WriteLine("Will download the next page.")
                End If
            Else
                Console.WriteLine("The last page is done.")
                Exit While
            End If
            unreadView.Offset = unreadItems.NextPageOffset
        End While

        Console.WriteLine()

        Console.WriteLine("Download unread messages, full messages with attachments")
        unreadItems = ewsClient.DownloadItems(unreadItems, EwsItemParts.MailMessageFull)
        For i As Integer = 0 To unreadItems.Count - 1
            Dim item As EwsItem = unreadItems(i)
            Console.WriteLine(String.Format("ID {0} size: {1}, attachments count: {2}, attachments: {3}",
                Shorten(item.UniqueId, 10), item.Size, item.MailBeeMessage.Attachments.Count,
                String.Join(", ", item.MailBeeMessage.Attachments.Cast(Of MailBeeAttachment)().Select(Function(a) Shorten(a.Filename, 20)))))

            ' For last message, do additional processing.
            If i = unreadItems.Count - 1 Then
                If item.MailBeeMessage.Attachments.Count > 0 Then
                    ' Save all attachments using MailBee.
                    item.MailBeeMessage.Attachments.SaveAll("C:\Temp", True)

                    ' Save a particular attachment using MailBee.
                    item.MailBeeMessage.Attachments(0).SaveToFolder("C:\Temp", True)
                End If

                If item.NativeMessage.Attachments.Count > 0 Then
                    ' Demonstrate working with attachments directly via Managed EWS API.
                    Console.WriteLine("  Attachment ID to name:  " &
                        String.Join(", ", item.NativeMessage.Attachments.Select(Function(a) ShortenId(a.Id) & ": " & Shorten(a.Name, 20))))
                    Dim fileAttachs As IEnumerable(Of FileAttachment) = item.NativeMessage.Attachments.OfType(Of FileAttachment)()
                    If fileAttachs.Count() > 0 Then
                        Console.WriteLine("  File attachment IDs: " & String.Join(", ", fileAttachs.Select(Function(fa) ShortenId(fa.Id))))
                        Dim fileAttach As FileAttachment = fileAttachs.First()
                        ' This will save attachment to disk.
                        fileAttach.Load(Path.Combine("C:\Temp", fileAttach.Name))
                    End If
                End If

                ' Add attachment to message and then delete it. This is a kind of action you can only do with EWS and not with POP3 or IMAP, for example
                ' (you cannot alter existing messages in POP3/IMAP, only mark them with flags).
                Console.WriteLine(String.Format("Attachment count: {0}", item.NativeMessage.Attachments.Count))
                Dim newAttach As FileAttachment = ewsClient.AddAttachmentToItem(item.Id, "C:\Temp\test.txt", "filename.txt")
                item.NativeItem.Load()
                Console.WriteLine(String.Format("Attachment count: {0}", item.NativeMessage.Attachments.Count))
                Console.WriteLine("Will delete attachment just added")
                Dim countAttachsDeleted As Integer = ewsClient.DeleteAttachment(item.Id, newAttach.Id, True, True)
                item.NativeItem.Load()
                Console.WriteLine(String.Format("Attachment ID: {0}, instances deleted: {1}", ShortenId(newAttach.Id), countAttachsDeleted))
                Console.WriteLine(String.Format("Attachment count: {0}", item.NativeMessage.Attachments.Count))

                Dim deleteOtherAttachs As Boolean = False
                ' Set to true to enable deletion of other attachments. Do this only in test accounts, not in your normal account!
                If deleteOtherAttachs Then
                    Console.WriteLine("Will delete the remaining attachments, if any")
                    ewsClient.DeleteAttachments(item.Id)
                    item.NativeItem.Load()
                    Console.WriteLine(String.Format("Attachment count: {0}", item.NativeMessage.Attachments.Count))
                End If

            End If
        Next
        Console.WriteLine()

        ' Update message flags to mark last message in the folder as unread (just to make sure the search for unread messages below will find at least one message).
        If inbox.TotalCount > 0 Then
            Dim item As EwsItem = ewsClient.DownloadItem(foldId, 0, EwsItemParts.IdOnly)
            item.IsRead = True
            ewsClient.UpdateItem(item)
        End If

        ' Clear keyboard buffer to avoid earlier Esc strokes alter the code flow below.
        While Console.KeyAvailable
            Console.ReadKey()
        End While

        Console.WriteLine("Search for unread messages via using SearchFilter")
        Dim filt As SearchFilter = Nothing ' "No filter" means "Search all messages".
        filt = New SearchFilter.IsEqualTo(EmailMessageSchema.IsRead, False) ' Modify filter to allow only unread messages.
        unreadItems = ewsClient.Search(foldId, filt)
        Dim unreadUids As String = String.Join(", ", unreadItems.Select(Function(it) ShortenId(it.UniqueId)))
        Console.WriteLine(Convert.ToString("Unread IDs (you can then pass them to DownloadItems): ") & unreadUids)
        Console.WriteLine()

        ' Simply display all messages in the folder with paging. We know in advance how many items to display so we don't need MoreAvailable and custom ItemView.
        Console.WriteLine("Display all messages in the folder in paged manner")
        Console.WriteLine("Press Esc to skip downloading the next page of messages (if any).")
        Console.WriteLine()
        Dim items As EwsItemList = Nothing
        While page * pageSize < inbox.TotalCount
            ' You can replace EwsItemParts.GenericItem with EwsItemParts.MailMessageFull to download full messages (with body/attachments) instead of basic info.
            ' If you do this replacement, item.MailBeeMessage will no longer be null.
            items = ewsClient.DownloadItems(foldId, page * pageSize, pageSize, True, EwsItemParts.GenericItem)
            For Each item As EwsItem In items
                If item.MailBeeMessage Is Nothing Then
                    Console.WriteLine(String.Format("To: '{0}', From: '{1}', Subject: '{2}', IsRead: {3}, Size: {4}",
                        Shorten(item.To, 20), Shorten(item.From, 20), Shorten(item.Subject, 20), item.IsRead, item.Size))
                Else
                    Console.WriteLine(String.Format("To: '{0}', From: '{1}', Subject: '{2}', IsRead: {3}, Size: {4}, MailBeeMessage.Size: {5}",
                        Shorten(item.To, 20), Shorten(item.From, 20), Shorten(item.Subject, 20), item.IsRead, item.Size, item.MailBeeMessage.Size))
                End If
            Next
            page += 1
            Console.WriteLine("------------")
            If Console.KeyAvailable AndAlso Console.ReadKey().Key = ConsoleKey.Escape Then
                Console.WriteLine("Esc pressed, will skip downloading the remaining pages and proceed to other examples.")
                Exit While
            End If
        End While

        ' Demonstrate working with deeply nested folders. EWS Managed API itself can only work with one level, MailBee adds this functionality on top of EWS.
        If Not ewsClient.FolderExists("Inbox/2nd level/3rd level") Then
            ' Create a deeply nested folder.
            ewsClient.CreateFolder("Inbox/2nd level/3rd level", Nothing)
            Console.WriteLine("Created folder ""Inbox/2nd level/3rd level""")
        End If
    End Sub
End Class

Reference

MailBee.EwsMail Namespace