A user sets up a vacation rule or auto-reply rule that is allowed to send to external recipients.
When a message from an external sender triggers the rule, that sender will receive an automated message back from <postmaster@domainname> instead of the <user@domainname> address.
In the GroupWise Admin console, browse to and click the GWIA.
Click the SMTP/MIME tab, then click Address Handling.Enable the option for: "Use GroupWise User Address as Mail From: for Rule Generated Messages:"
Click Save, then click Close to return to the main Admin console window.
After the GWIA restarts, all auto-reply messages will not be sent from the <user@domainname> address.