(VB.NET) POP3 to SMTP Forwarder

Read a POP3 mailbox and forwards the email to another email address, keeping the recipients in the original email the same.

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

Dim mailman As New Chilkat.MailMan

Dim success As Boolean

' Set the POP3 server's hostname
mailman.MailHost = "pop.example.com"

' Set the POP3 login/password.
mailman.PopUsername = "MY_LOGIN"
mailman.PopPassword = "MY_PASSWORD"

Dim saUidls As Chilkat.StringArray

' The the UIDLs for all email in the POP3 mailbox.
saUidls = mailman.GetUidls()
If (mailman.LastMethodSuccess = False) Then
    Debug.WriteLine(mailman.LastErrorText)
    Exit Sub
End If


Dim saMime As Chilkat.StringArray

' Download the email from the server.  Call FetchMultipleMime
' because we don't want to load the emails into email objects.
' (We'll delete the emails that are forwarded without error.)
' Note: It is not reasonable to call this method for a mailbox containing
' a huge number of emails.  For large mailboxes, it's better to download
' one by one and process each email independently. This way, if a 
' server or communications error occurs, it's possible to write code
' that can resume.
saMime = mailman.FetchMultipleMime(saUidls)

If (mailman.LastMethodSuccess = False) Then

    Debug.WriteLine(mailman.LastErrorText)
    Exit Sub
End If


' Set the SMTP hostname for sending.
mailman.SmtpHost = "smtp.example.com"
mailman.SmtpUsername = "MY_SMTP_LOGIN"
mailman.SmtpPassword = "MY_SMTP_PASSWORD"


Dim n As Integer = saMime.Count

Dim fromAddr As String = "me@example.com"
Dim toAddr As String = "recipient@somewhere.com"

Dim bAllOk As Boolean = True

Dim i As Integer = 0
While i < n

    Dim strMime As String = saMime.GetString(i)

    ' Forward the email.
    success = mailman.SendMime(fromAddr,toAddr,strMime)
    If (success <> True) Then
        bAllOk = False
        Debug.WriteLine(mailman.LastErrorText)
        ' Force loop exit.
        i = n
    End If


    i = i + 1
End While

' Remove the emails in saUidls from the POP3 server.
If (bAllOk = True) Then
    success = mailman.DeleteMultiple(saUidls)
    If (success <> True) Then
        Debug.WriteLine(mailman.LastErrorText)
    End If

End If





Debug.WriteLine("bAllOk = " & bAllOk)