Like others, I've been a loyal Avast user and advocate for many years, but feel I had no choice but to jump ship this morning. I updated to 2011 a week ago that essentially made browsing impossible as long as web shield was active. Everything worked normally when switched off, and System Restore was able to revert Avast to the previous version. Though probably of no help, I posted my experiences. I've since learned that even the previous "good" version was erroneously blocking some websites.
I made sure that Program Update was set to Manual to avoid a possible automatic update, but this morning the web shield was disabled. Hitting "REPAIR" installed 2011 all over again; and the problems previously encountered reappeared. Unfortunately, System Restore didn't this time, but the Avast removal tool finally got rid of the program in the Safe Mode.
I'd love to be able to help troubleshoot the problem, but if had been earning just minimum wage for the hours I've already spent troubleshooting and trying to restore the computer after the 2011 update episodes, I could have bought any of the full version antivirus programs out there! NOT everyone is a computer geek or has the knowledge, time, or inclination to dive into the inner workings of their machines … and that's even if there was a reliable repair. They simply expect their antivirus program to work or at least not screw things up.
Perhaps I'm mistaken and the Avast crew is really taking these problems seriously, but excusing the matter by saying that "most people don't have any issues" is condescending and likely without basis in fact. Most users don't have a clue what's wrong when their computer experiences any of the problems being enumerated in this forum. Most don't even know there is a forum! They're screwed without even knowing the cause!
I'll keep monitoring and hoping this issue will be resolved; possibly I'll return to Avast. I really liked it, not to mention the sexy definition update announcements! Now to take care of my other five computers that also have Avast, not to mention the several computers I routinely maintain for others.