Why do the trojans keep coming back after I do a full scan?

Hi guys,

I had a bunch of viruses on my computer a few weeks ago - I got MBAM, spybot S&D, ccleaner, & HijackThis & tried to get rid of everything.

Now when I run MBAM & Avast - the scan is currently showing up clean. But when I run a full scan with Spyware Doctor - a bunch of trojans keep reappearing.

This morning, there are atleast 2 trojans (scan's not complete yet) I found w/ spyware doctor:

trojan-downloader.murlo
trojan.generic

Why do the trojans keep reappearing? (Last night - I used ComboFix)

Reply 1 : Why do the trojans keep coming back after I do a full scan?

Having a dupe just confuses things.

Original thread
http://forums.cnet.com/7723-6132_102-523711.html

I am locking this one