Relay Access Denied - 2008 Version

Whenever I try to send mail to any of the sites I’ve set up with VirtualMin I get several errors one of which is “relay access denied”. I have checked everything but I am guessing I’ve missed something. Can anyone give me a few places to look at? Below is part of the text from the error. I send an email to one of my other email accounts on another server and when I replied to the message, I got the error

----- The following addresses had permanent fatal errors ----- <beverly@mydomain.com> (reason: 554 5.7.1 <beverly@mydomain.com>: Relay access denied)

----- Transcript of session follows -----
… while talking to mail.mydomain.com.:
>>> DATA
<<< 554 5.7.1 <beverly@mydomain.com>: Relay access denied
554 5.0.0 Service unavailable
<<< 554 5.5.1 Error: no valid recipients

Final-Recipient: RFC822; beverly@mydomain.com
Action: failed
Status: 5.7.1
Remote-MTA: DNS; mail.mydomain.com
Diagnostic-Code: SMTP; 554 5.7.1 <beverly@mydomain.com>: Relay access denied
Last-Attempt-Date: Sat, 15 Nov 2008 08:14:12 -0500 (EST)

If everything is set to default setting and you are using Postfix, make sure you are selecting "My server requires authentication" in the email client program.

Or add your local IP range to "Mynetworks" in postfix so that Postfix knows it may relay email from those addresses.

Steve

I got him sorted out now and he his emails are getting delivered.