"554 this message has already been here"?

[partha]

not really an html/browser question, but I thought you guys might know the answer:

A client told me that he tried to send a message to an email address I set up for his company and got the following message:

"554 this message has already been here"

The email address he send to has worked in the past. So what is the problem, and any ideas how I can fix it?

thanks

[jdMorgan]

Look for a forwarding-address loop. For example Address A forwarding to Address B which forwards to Address A.

Jim