KB01120902 Autoresponding to external mail only

It's impossible to avoid sending an autoresponse if you use an autoresponse template. The trick lies in suppressing the unwanted output messages.

You do need to add a routine to the autoresponder but that's not very difficult. Insert the following four lines right after the existing SelectOutMessage() line in the autoresponse template ...

 host_list := GetSystemVar("/HostAliases") ++ "\n" ++ LOCALHOST ++ " ";
 If(WildcardMatch(host_list, HostOf(Header("To"))),
   SetHeader("X-Route", "dev/nul")
 );

Then create a script named devnul in Mailtraq which will remain entirely empty. Register the script on the Automated Scripting tab to act on the Message:Routing trigger and, on the Message Trigger tab, uncheck "Script will modify the message" and check "Handoff to script." Click on Filter and complete as follows ...

 Criteria  [ X-Route ]  Value  [ dev/nul ]
 Match  [ Any ]

... after which any message with an X-Route header containing "dev/nul" will be dropped on the floor at Mailtraq's inbound router.

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