There is something that has been going around the reptile community. It is called Kakworm. Antivirus programs will not stop it. It will eventually shut your email down completely. Here is a link with instructions for checking your computer and removing it. Afterwards if you are using Outlook Express you need to got to www.microsoft.com and download the latest patch for it and it will prevent the worm from re-infecting.
http://www.sarc.com/avcenter/venc/da...kworm.fix.html