(Visual Basic 6.0) POP3 Verify Signed (S/MIME) Email

Demonstrates how to download and verify digitally signed S/MIME email.

Note: This example requires Chilkat v11.0.0 or greater.

Chilkat ActiveX Downloads ActiveX for 32-bit and 64-bit Windows

Dim success As Long
success = 0

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

Dim mailman As New ChilkatMailMan

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

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

Dim stUidls As New ChilkatStringTable
success = mailman.FetchUidls(stUidls)
If (success = 0) Then
    Debug.Print mailman.LastErrorText
    Exit Sub
End If

Dim email As New ChilkatEmail
Dim cert As New ChilkatCert

Dim count As Long
count = stUidls.Count
Dim i As Long
i = 0
Do While i < count
    ' Download the full email.
    success = mailman.FetchByUidl(stUidls.StringAt(i),0,0,email)
    If (success = 0) Then
        Debug.Print mailman.LastErrorText
        Exit Sub
    End If

    Debug.Print i
    Debug.Print "From: " & email.From
    Debug.Print "Subject: " & email.Subject

    ' The security layers of signed and/or encrypted emails
    ' are automatically "unwrapped" when loaded into
    ' a Chilkat email object.
    ' An application only needs to check to see if an email
    ' was received signed or encrypted, and then examine
    ' the success/failure.  For example:
    If (email.ReceivedSigned = 1) Then

        Debug.Print "This email was signed."

        ' Check to see if the signatures were verified.
        If (email.SignaturesValid = 1) Then
            Debug.Print "Digital signature(s) verified."
            Debug.Print "Signer: " & email.SignedBy

            success = email.LastSignerCert(0,cert)
            If (success = 0) Then
                Debug.Print email.LastErrorText
                Exit Sub
            End If

            Debug.Print "Signing cert: " & cert.SubjectCN
        End If

    Else
        Debug.Print "Digital signature verification failed."
    End If

    i = i + 1
Loop

success = mailman.Pop3EndSession()