I am trying to relay email thru my provider that has a mail server for my domain (xxxx.com). My postfix is configured as follows:
relayhost = [smtp.xxxx.com]:25
the server requires authorization, but it is working correctly.
> smtp.xxxx.com[79.96.129.xxx]:25: AUTH PLAIN AewfewfewfcewfewfewfbwBLYnNKazY1UVUjZnc=
< smtp.xxxx.com[79.96.129.xxx]:25: 235 2.7.0 User mailing+xxxx_com logged in.
The problem is: the relay server REQUIRES "MAIL FROM:" to be set to the same user I use for authenticaton. But the user is by default different.
> smtp.xxxx.com[79.96.129.xxx]:25: MAIL FROM:<user@server.xxxx.com> SIZE=296
< smtp.xxxx.com[79.96.129.xxx]:25: 550 5.1.8 Sender address rejected
The question is: how to make my local postfix to user "MAIL FROM:" as a user from relaying server regardless the local user that sends the mail?
Thanks!