Trojan Horse's Disappears on my computer?

Okay, so I scanned using Norton Anti-Virus first, and found 3 virus's in my temporary internet folders. I downloaded AVG and scanned, it only found 2 the next time. I then scanned AVG and Norton for the 2nd time, andnothing appears. Norton keeps saying that Hacktool.rootkit keeps trying to attack or something, so it comes up with a warning message. How cani get of it? and are they actually there?

Trojan Horse's Disappears on my computer?liveupdate

Firstly get rid of one of the antivirus programs. I would recommend keeping Norton as it has an excellent pick up rate.

Now download Hijack This! from www.merjin.org and scan ure comp in safe mode using that. then upload the log to the trend micro forums and see what the folks there say.

Download a good firewall as well, like zone alarm and then block all internet activity and see what tries to access the net.

Also download Ad - Aware SE or Spyware terminator to get rid of any spyware youve got.

Trojan Horse's Disappears on my computer?nortin

The reason AVG detects only 2 is because trojans/hacks are created in order to hide from certain virus scanners. And when nothing appears after scanning it again, trojans have the ability to move to certain files and corrupt others... They hide and slowly corrupt other files.