Hi, myxpc, and welcome to LQ.
The problem is due to your
mydestination parameter in main.cf. That parameter lists the domains that will be delivered locally. Here's an example:
Code:
myhostname = machine.example.com
mydestination = $myhostname, localhost.$mydomain, localhost, $mydomain, example2.com
This means that the following domains will be delivered locally: machine.example.com, localhost.example.com, localhost, example.com, example2.com.
Code:
<<< 554 5.7.1 <postmaster@mydomain>: Relay access denied
This means postfix doesn't know that it should deliver mail to that domain locally. List it in
mydestination.