Problem with file

Can someone post a sample file for me? I can send email outside
of my system, but the sender address comes across all distorted. Instead of
user@nodename, I get user%nodename.ip address@ The problem is that some
systems are rejecting these emails because they do not follow the standard.
I bought the “bat” book and have been trying to edit the file on my own to
no avail. I figured if it is working on someone else’s system I can try
that one and also compare it to my own to see the differences.