Hope someone can help with this, as I'm stumped. This message could get a bit long, so please bear with me! I recently started getting loads of "undeliverable mail" messages returned to my email account supposedly from emails I've never sent. I tried a load of anti-virus products (full list below) and none of them found anything. I downloaded a trial version of PC Door Guard which reported the virus "EXE2BIN" in c:\windows\system32\exe2bin.exe. I tried deleting the file, but it reports the file is in use and can't be deleted. I tried re-installing Windows and with nothing else installed other than DoorGuard, the virus is still reported. I know exe2bin.exe is a legit Windows file, and wonder whether DoorGuard is identifying a false positive or whether my Windows file has been replaced by something malicious. For the record, I've scanned using full versions of Sophos, Adaware and Spybot, the free versions of AVG and AVAST and trial versions of TDS and PC Doorguard. PC Doorguard is the only one that picks anything up. Out of interest, I also took a copy of the file c:\Windows\System32\exe2bin.exe from 8 different PCs at work and a friend's PC. When scanning through DoorGuard, they are all reported as infected. I phoned the Microsoft free security helpline, but they'd never heard of the virus. I also tried emailing AstonSoft, the producers of DoorGuard. However, after 4 days, my email was returned as undeliverable because their mailbox is full. Is exe2bin really a virus or is it DoorGuard reporting a false positive? If it is a virus, any advice on getting rid of it would be much appreciated. I've tried everything I can think of and can't get anywhere!