[@tjworld Member 16 years, 10 months ago]

I’ve just encountered this with 0.8.3.1. As the mail server administrator I was getting delivery failure notifications which reported that the receiving SMTP host had rejected the email with:

<xxxxx@aol.com>: host mailin-04.mx.aol.com[64.12.138.57] said: 501 SYNTAX

ERROR IN PARAMETERS OR ARGUMENTS (in reply to MAIL FROM command)

I increased logging on Postfix and tested it and found:

mailin-04.mx.aol.com[64.12.138.57]: MAIL FROM:<yyyyyyyy@localhost>

mailin-04.mx.aol.com[64.12.138.57]: 501 SYNTAX ERROR IN PARAMETERS OR ARGUMENTS

Where ‘yyyyyyyy’ is the mail server’s local user account for the domain doing the sending.

It looks as if the AOL server is rejecting the @localhost part of the MAIL FROM field. I’ve looked in the bbPress config.php and in the administration options of the dashboard but can’t see why bbPress is using localhost.