Malformed container virus

My friend has tried to send 2 separate emails to the same person and keeps getting something back from the other person's isp (Earthlink) saying that the messages she sent were intercepted and quarantined because they contained the Malformed container virus. What is this and how do I get rid of it for her? ANy help or info appreciated.

 

I read a few reports on the web about malformed container viruses. And after reading a report from virus bulliten. I believe that it means it is a malformed file virus. Your friend needs to try a few online virusscans to see if she can find out which file is infected unless her virusscan can find it.
here are a few free online scans

http://housecall.trendmicro.com/


http://www.bitdefender.com/scan/licence.php


http://www.pandasoftware.


http://www.kaspersky.com/service.html?chapter=595517