[ObsoleteAttribute("This method is obsolete in .NET 4.5+. Use AuthPopBeforeSmtpAsync instead.")]
public IAsyncResult BeginAuthPopBeforeSmtp(
	string pop3ServerName,
	int pop3ServerPort,
	string pop3AccountName,
	string pop3Password,
	AsyncCallback callback,
	Object state
)

<ObsoleteAttribute("This method is obsolete in .NET 4.5+. Use AuthPopBeforeSmtpAsync instead.")>
Public Function BeginAuthPopBeforeSmtp ( 
	pop3ServerName As String,
	pop3ServerPort As Integer,
	pop3AccountName As String,
	pop3Password As String,
	callback As AsyncCallback,
	state As Object
) As IAsyncResult

// To use the code below, import MailBee namespaces at the top of your code.
using MailBee;
using MailBee.SmtpMail;

// Put the code below inside your class.

// The actual code.
private void Form1_Load(object sender, System.EventArgs e)
{
    Smtp mailer = new Smtp();

    // Let MailBee process events.
    mailer.RaiseEventsViaMessageLoop = false;

    mailer.SmtpServers.Add("mail.domain.com");

    // Initiate an asynchronous POP-before-SMTP authentication attempt.
    mailer.BeginAuthPopBeforeSmtp("mail.domain.com", 110, "jdoe", "secret", null, null);

    // Simulate some lengthy work here...
    for (int i = 0; i < 100; i++)
    {
        // Make a portion of the work.
        System.Threading.Thread.Sleep(10);

        // Process events which were raised during execution of the work above.
        mailer.Wait(0);
    }

    // End the POP-before-SMTP operation. If it's in progress at the moment 
    // this method starts, it will wait until it's done first.
    mailer.EndAuthPopBeforeSmtp();

    // Connect to SMTP server and say Hello.
    mailer.Connect();
    mailer.Hello();

    // Can send mail here or do whatever needed.
    // ...

    // Close the connection.
    mailer.Disconnect();
}

' To use the code below, import MailBee namespaces at the top of your code.
Imports MailBee
Imports MailBee.SmtpMail

' Put the code below inside your class.

' The actual code.
Private Sub Form1_Load(ByVal sender As Object, ByVal e As System.EventArgs)
    Dim mailer = New Smtp

    ' Let MailBee process events.
    mailer.RaiseEventsViaMessageLoop = False

    mailer.SmtpServers.Add("mail.domain.com")

    ' Initiate an asynchronous POP-before-SMTP authentication attempt.
    mailer.BeginAuthPopBeforeSmtp("mail.domain.com", 110, "jdoe", "secret", Nothing, Nothing)

    ' Simulate some lengthy work here...
    For i As Integer = 1 To 100
        ' Make a portion of the work.
        System.Threading.Thread.Sleep(10)

        ' Process events which were raised during execution of the work above.
        mailer.Wait(0)
    Next

    ' End the POP-before-SMTP operation. If it's in progress at the moment 
    ' this method starts, it will wait until it's done first.
    mailer.EndAuthPopBeforeSmtp()

    ' Connect to SMTP server and say Hello.
    mailer.Connect()
    mailer.Hello()

    ' Can send mail here or do whatever needed.
    ' ...

    ' Close the connection.
    mailer.Disconnect()
End Sub