Win32:trojano-850, win32:trojano-851

Avast found on my hard disk these two trojans:

win32:trojano-851
win32:trojano-850

I can’t move them to basket, but I can erase them. The fact is that everytime I reboot and then connect to the internet, it seems that they appear again under different file name. They are always located in windows/system directory under a strange .dll file name. Everytime it changes its name.

Any advice or information about these two trojans and how to definetely erase them?

Click on the link in my signature and follow the instructions in the malware removal section.
Let us know if that solved the problem.