Problem with Trojans

Hi,

This is about the third year that I have been using NIS, and I have never had a problem like I have now. NIS didn't alert me at the time of entry unfortunately, but it appears that  I have a number of Trojans secreted away on my computer.

Initially a complete scan suggested that there were 7 instances of a problem virus, but by spending all day so far, and trying various remedies it's now down to 4. I can't get rid of them no matter what I try. I did download and run Power Eraser, but I am still left with four instances of an infection.

Currently the problem viruses are - Trojan.Gen, and Backdoor.Trojan. There are two instances of each.

I have lost count of the number of complete scans that I have run, but the common denominators are that apparently all the offending files are supposedly .zip files, and clicking on 'Location' in the scan results seems to point to the junk folder of my e-mail client, suggesting that is where they are. By the way, I use Thunderbird as my e-mail client. Part of the 'path' that the scan results suggest is as follows:

....\Profiles\u4yej5df.default\Mail\pop.mail.yahoo-2.com\\Junk

The only problem is that my actual Junk folder in the visible e-mail client is empty, as far as I can see.

What can I do now? How do I get rid of the pesky little blighters?

I hope someone can help.

Regards,

Alan