(VB.NET UWP/WinRT) Bounced Email Handling

Demonstrates how to examine emails and detect which are bounced (automated) replies. Classifies each email according to the type of bounce.

Chilkat Universal Windows Platform (UWP) / WinRT Downloads Chilkat for the Universal Windows Platform (UWP)

' This example requires the Chilkat API to have been previously unlocked.
' See Global Unlock Sample for sample code.

Dim bounce As New Chilkat.Bounce

' The mailman object is used for receiving (POP3) 
' and sending (SMTP) email.
Dim mailman As New Chilkat.MailMan

' Set the POP3 server's hostname
mailman.MailHost = "mail.chilkatsoft.com"

' Set the POP3 login/password.
mailman.PopUsername = "myLogin"
mailman.PopPassword = "myPassword"

' Copy the all email from the user's POP3 mailbox 
' into a bundle object.  The email remains on the server.
' (There are other methods for deleting email from a POP3 server.)
Dim bundle As Chilkat.EmailBundle = Await mailman.CopyMailAsync()
If (mailman.LastMethodSuccess = False) Then
    Debug.WriteLine(mailman.LastErrorText)
    Exit Sub
End If


Dim i As Integer = 0
Dim email As Chilkat.Email
While i < bundle.MessageCount
    email = bundle.GetEmail(i)

    Dim success As Boolean = bounce.ExamineEmail(email)
    If (success = False) Then
        Debug.WriteLine(bounce.LastErrorText)

        Exit Sub
    End If


    If (bounce.BounceType = 1) Then
        ' Hard bounce, log the email address
        Debug.WriteLine("Hard Bounce: " & bounce.BounceAddress)
    End If

    If (bounce.BounceType = 2) Then
        ' Soft bounce, log the email address
        Debug.WriteLine("Soft Bounce: " & bounce.BounceAddress)
    End If

    If (bounce.BounceType = 3) Then
        ' General bounce, no email address available.
        Debug.WriteLine("General Bounce: No email address")
    End If

    If (bounce.BounceType = 4) Then
        ' General bounce, log the email address
        Debug.WriteLine("General Bounce: " & bounce.BounceAddress)
    End If

    If (bounce.BounceType = 5) Then
        ' Mail blocked, log the email address
        ' A bounce occured because the sender was blocked. 
        Debug.WriteLine("Mail Blocked: " & bounce.BounceAddress)
    End If

    If (bounce.BounceType = 6) Then
        ' Auto-reply, log the email address
        Debug.WriteLine("Auto-Reply: " & bounce.BounceAddress)
    End If

    If (bounce.BounceType = 7) Then
        ' Transient (recoverable) Failure, log the email address
        Debug.WriteLine("Transient Failure: " & bounce.BounceAddress)
    End If

    If (bounce.BounceType = 8) Then
        ' Subscribe request, log the email address
        Debug.WriteLine("Subscribe Request: " & bounce.BounceAddress)
    End If

    If (bounce.BounceType = 9) Then
        ' Unsubscribe Request, log the email address
        Debug.WriteLine("Unsubscribe Request: " & bounce.BounceAddress)
    End If

    If (bounce.BounceType = 10) Then
        ' Virus Notification, log the email address
        Debug.WriteLine("Virus Notification: " & bounce.BounceAddress)
    End If

    If (bounce.BounceType = 11) Then
        ' Suspected bounce.
        ' This should be rare.  It indicates that the Bounce
        ' component found strong evidence that this is a bounced
        ' email, but couldn't quite recognize everything it
        ' needed to be 100% sure.  Feel free to notify
        ' support@chilkatsoft.com regarding emails having this
        ' bounce type.
        Debug.WriteLine("Suspected Bounce!")
    End If

    If (bounce.BounceType = 12) Then
        ' Challenge/Response - Auto-reply message sent by SPAM software 
        ' where only verified email addresses are accepted. 
        Debug.WriteLine("Challenge: " & bounce.BounceAddress)
    End If

    If (bounce.BounceType = 13) Then
        ' Address Change Notification Message.
        Debug.WriteLine("Address Change: " & bounce.BounceAddress)
    End If

    If (bounce.BounceType = 14) Then
        ' Success DSN indicating that the message was successfully relayed.
        Debug.WriteLine("DSN Successful Relay: ")
    End If




    i = i + 1
End While



success = Await mailman.Pop3EndSessionAsync()