We have recently moved web server to Win2k3 and I have noticed that emails going through our server from aol.com email addresses are getting bounced with the message:
Diagnostic-Code: smtp;550 aol.com sender, but not from a publicised relay.
Is this happening because an AOL user has sent an enquiry form from one of our sites but not actually been logged into AOL at the time of sending?
Is there some way I can fix this as I cannot find anything on the web to help resolve this issue. It's important to resolve this because a lot of our large clients are receiving legitimate emails from AOL.com users.
Thanks in advance,