I have had two similiar stories:
It was installed avast! 4.7 pro on clean computer 2 months ago. No problems, scanned whole HDD. Default settings. After 2 months broblems started because infected files with Sality wirus. Avast warn about infection but couldn’t delete infected files. I rebotted PC and scanned in dos-mode. Avast found a few infected files and deleted it. Aften run again in windows normal mode problems started again. Any dll files (mnmgr32 as I remember) infected. And again and again. I wasn’t be able to remove Sality viruses from my friend’s PC. I cured it only by any online scanner. This scanner found many many more infected files on HDD. My question is: if avast! known this virus definition (warn me about Sality infection), why it let virus to infect my computer? Shoul I change default settings to protect by known viruses protection?
Today another one problem:
One time ago (4 months?) I installed avast Home on my friend’s PC. Today, he call me his PC is infected. I checked it. PC couldn’t run in normal mode, only safe mode. Avast DOS scanner during boot found this:
E:\Program Files\NewDotNet\newdotnet7_22.dll [L] Win32:Spyware-gen. [Trj] (0)
. After remove this files, I still can’t run windows in normal mode. And again: why avast not protect PC against this virus? All of this avast was updated (broadband internet connection)
P.S. sorry for my english 