If you have not already heard, Avast has some fancy footwork to do and a lot of explaining. I read on another forum (in a closed area) about Avast offering an update that was trashing computers right and left. It was finding EVERYTHING as a virus, including system files. It was putting them in it's quarantine area and then you couldn't get it out. If you re-booted, it was even more of a nightmare.
One user ended up with the entire protected area of his system corrupted and trashed, including system restore!
Avast has corrected the problem and if you were lucky enough to be an Avast user with the computer OFF during the interim, you were fine. Otherwise, cross your fingers.
The information about the problem is ONLY in Avast's forum. There has been no public apology on their main site. They say they've corrected it and are working to see it doesn't happen again and they are posting helps to get people back.
What they can do to those who have corrupted systems (with no system disk - HP doesn't provide them), I don't know but I think their headaches are just starting.
A few links about the problem:
Discussion of the False Positive: http://www.dslreports.com/forum/r23428578-False-positive-in-Avast-or-is-it-real
Official Response: http://forum.avast.com/index.php?topic=51647.msg436938#msg436938
First "Help": http://support.avast.com/index.php?_m=knowledgebase&_a=viewarticle&kbarticleid=377
Third Party Report: http://www.pcmag.com/article2/0,2817,2356600,00.asp
I'm glad I don't use Avast (I use Avira)
WHEW!
Diane
