This step-by-step article shows how to use an SMTP transport event sink to add a disclaimer to outgoing SMTP e-mail messages.

If Msg.HTMLBody <> "" Then

'Search for the "</body>" tag and insert our discliamer before that tag.
pos = InStr(1, Msg.HTMLBody, "</body>", vbTextCompare)

szPartI = Left(Msg.HTMLBody, pos - 1)

szPartII = Right(Msg.HTMLBody, Len(Msg.HTMLBody) - (pos - 1))

Msg.HTMLBody = szPartI + HTMLDisclaimer + szPartII

End If

If Msg.TextBody <> "" Then

Msg.TextBody = Msg.TextBody & vbCrLf & TextDisclaimer & vbCrLf

End If

'Commit the content changes to the transport ADO Stream object.
Msg.DataSource.Save
' Commit the changes into the transport Stream
pEventStatus = cdoRunNextSink

Register the event sink
To register your event sink, use the Smtpreg.vbs file, which is installed with the Exchange SDK. From a command prompt, browse to the ...Exchange SDKSDKSupportCDOScripts folder and type the following (make sure that the path to EventSinkScript.vbs is correct): 

cscript smtpreg.vbs /add 1 onarrival SMTPScriptingHost CDO.SS_SMTPOnArrivalSink "mail from=*@your-domain-here.com"

cscript smtpreg.vbs /setprop 1 onarrival SMTPScriptingHost Sink ScriptName "C:EventSinkScript.vbs"

If the command succeeds, you receive a success message generated by the script.

To register your event sink, use the Smtpreg.vbs file, which is installed with the Exchange SDK. From a command prompt, browse to the ...Exchange SDKSDKSupportCDOScripts folder and type the following (make sure that the path to EventSinkScript.vbs is correct): If the command succeeds, you receive a success message generated by the script.

To unregister this event, type the following:

cscript smtpreg.vbs /remove 1 OnArrival SMTPScriptingHost 

Test the event sink

To test your sink, send an e-mail message to an SMTP recipient who is external to your organization. The recipient should receive a modified message with the disclaimer added to the end of the message.

Note If you use a MAPI client such as Microsoft Outlook to send the e-mail, the recipient does not receive a modified message. This is because messages submitted using MAPI are not in SMTP format when the e-mail triggers the SMTP transport event. Therefore, changes that are made by the event's code are not persisted.