SISZYD32.exe is a rootkit... much more harmful than your standard Trojan. It’s the reason why your antivirus didn’t catch it in the first place. If in fact you have this rootkit, then a lot of your Windows system files have been overwritten, which is how it remains in your system despite attempting to clean it up. It’s going to be a tough process, but try the resolution given in the Avast forums. Rootkits can’t be quickly removed like virii or trojans.
http://forum.avast.com/index.php?PHPSESSID=d56f2b6f315d12b523b4ba3de4a8e0f1&topic=52134.15
How did you get it if you only browsed FR? Did you read any articles posted on external sites? Some of these can easily be hidden in java/adobe pdf addons for IE and even Firefox. It only takes one.
Sophos and AVG have [free] rootkit removers.
I’ve never had to use them, but I do have them on my computer.
Yeah, ergo "the sites it cites" on the post. This pc is the one that goes everywhere. Running McAffee Site Advisor - http://www.siteadvisor.com/. Just got it and hadn't put it the victim pc.
Never heard of "rootkit."