MailBee.NET IMAP Component

MailBee.NET IMAP Component

Manage, download, search and process mails and folders on IMAP4 servers
MailBee.NET Objects bundle includes SMTP, POP3, IMAP, EWS, Security, Antispam, Outlook Converter, Address Validator, PDF components and also BounceMail, HTML, MIME, ICalVCard components which are a free functionality.

MailBee.NET IMAP is a high-performance memory-conservative .NET component for processing mails and folders on IMAP4 servers. The component can do everything the POP3 component does, and much more: download and manage folders, search, flag, upload, move, copy messages, download message envelopes or any specific parts or attributes of messages, etc.

MailBee.NET IMAP downloads messages in a batch, drastically improving performance.

MailBee.NET IMAP bundle includes a set of MIME objects such as MailMessage and Attachment which are used for e-mail parsing.

Visual Studio


Written in 100% managed code, MailBee.NET IMAP only requires the .NET framework be installed on the computer.

MailBee.NET IMAP can be used in any .NET language including C# and VB.NET. Supported .NET frameworks include .NET 2.0/3.0/3.5/4.0/4.5/4.6, both 32-bit and 64-bit.

MailBee.NET also supports .NET Core 1.0/1.1 including ASP.NET Core and Xamarin, UWP (Universal Windows).

With MailBee.NET Objects license, you also get these MailBee.NET components for free: BounceMail, HTML, MIME, ICalVCard.

MailBee.NET IMAP Component fully supports:


  • HTTP
  • SASL
  • NTLM
  • Kerberos
  • SOCKS4/5
  • HTTP Proxy



Servers & Services

  • MS Exchange
  • Lotus Notes
  • GroupWise
  • IMail
  • MailEnable
  • AxiGen
  • SmarterMail
  • SurgeMail
  • MDaemon
  • Kerio
  • CommuniGate
  • hMailServer
  • Qmail
  • Courier
  • Dovecot
  • Cyrus
  • Zimbra
  • GMail
  • Yahoo

...and any POP3/SMTP/IMAP compliant servers

IMAP Object

  • Download entire messages, headers only, envelopes, or anything else which can be returned by IMAP's FETCH command
  • Download and manage folders (international folder names fully supported)
  • Get special folder flags like Sent, Drafts, Trash (if server supports XLIST)
  • Download messages through a proxy server
  • Get already downloaded messages/envelopes if the entire operation failed in the middle
  • Supports secure TLS/SSL connections out-of-box (supports Gmail, etc)
  • Async/await methods
  • Upload a message in a folder
  • Copy messages between folders
  • UNIQUE Move messages between folders
  • UNIQUE Obtain UID of uploaded/copied/moved messages if the server supports UIDPLUS
  • Delete messages
  • Examine and set message flags
  • Expunge (i.e. purge) deleted messages
  • UNIQUE Expunge specific deleted messages
  • Search messages
  • Search and sort messages if IMAP SORT is supported by the server
  • IDLE mode to get notifications from the server on mailbox status change
  • Secure authentication (CRAM-MD5, DIGEST-MD5, NTLM, Kerberos)
  • UNIQUE Windows Integrated Authentication (authenticate using the current Windows user credentials)
  • User-defined authentication methods
  • UNIQUE Get account quota and used space size if the server supports QUOTA
  • Automatic detection and use of IMAP capabilities
  • UNIQUE Faster upload if the server supports LITERAL+
  • UNIQUE Can tolerate incorrectly formatted responses from the server (keeping the application informed if this happens)
  • Provides methods for converting IMAP strings, dates, international folder names, etc
  • Logging IMAP session into a file or memory
  • Returns e-mails as MailMessage objects which can be interchanged with other objects (Smtp, etc)
  • Can check DomainKeys/DKIM signatures of e-mails (using SMTP component)
  • Parses bounced e-mails and delivery notifications
  • Send user-defined commands to the server
  • Rich set of events and asynchronous processing options
  • Can be placed on the form or created in the code

Imap Object reference...

MailMessage Object

  • Import and export from/into System.Net.Mail.MailMessage
  • Used by Smtp object as outgoing e-mail
  • Returned by Pop3 and Imap objects as incoming e-mail
  • Multiple recipients (To/CC/BCC)
  • Multiple attachments
  • Advanced mail merge
  • Can be encrypted, signed, decrypted, or verified with Smime object
  • Easy access to plain-text and HTML body
  • Full support of international encodings and charsets
  • Can extract attachments from MS-TNEF (winmail.dat) files
  • Access to every MIME part
  • Access to all message headers
  • Access to message timestamps ("Received:" headers)
  • UNIQUEConversion from HTML to plain-text and vice versa including high-lighting of URIs, images, quotations, etc
  • UNIQUEFull support of creating and displaying HTML messages with embedded pictures in desktop and web applications
  • UNIQUEAccess forwarded messages (GetEncapsulatedMessage)
  • Forward message as attachment
  • Import HTML file or web page into e-mail
  • Import & export message data from/into memory, file and stream
  • Serialize into XML and deserialize from XML
  • Base64 and Quoted-Printable
  • Confirm Read & Confirm Receipt
  • Reply-To, Priority, Importance, Sensitivity, etc

MailMessage Object reference...

What's new

Version 11.0

  • .NET Core 1.0/1.1, .NET Standard 1.3+, ASP.NET Core support.
  • UWP (Universal Windows, UAP 10.0) support.
  • .NET 3.5 and .NET 4.0 builds (in addition to .NET 2.0 and .NET 4.5).
  • SHA256 signatures of all DLLs (in addition to SHA1).
  • IDN domains (e-mail addresses with international addresses).
  • Imap.GetSpecialFolder method to easily locate folders like Sent Items or Drafts.
  • TlsAuto mode to automatically select TLS 1.2 if possible and fall back to TLS 1.1 or 1.0 if not.
  • SocketCreating event to control how socket objects are created.
  • MailMessage.Sender property.
  • MailMessage.GetHtmlWithBase64EncodedRelatedFiles method.
  • Tested with Visual Studio 2017.

See Version History for details

Version 10.0

  • Async/await methods.
  • Xamarin Mono, Android, iOS support.
  • .NET 4.5 optimized edition.
  • TLS 1.1 and TLS 1.2 support.
  • Bounce database in memory (instead of a set of XML files).
  • Improved I/O performance with increased TCP buffers.
  • Tested with Windows 10, Visual Studio 2015, .NET Framework 4.6.

Clients Say:

"I've been looking at the MailBee.NET application and love it." Matt Yeager
"Thanks again for your help. I like your products..." Ron Hill
"By the way I love your software. Great work thank you." Dennis Drogemuller