ratpit, I experienced the same problem today, except that I was upgrading from version 131016-0, not to it.

I came here looking for help. Unfortunately the generic boilerplate response above was pretty unhelpful. The poor guy was looking for help with a specific problem. So after searching the web and finding a solution I took the time to register here to post the solution for others who find themselves in this frustrating situation.

Download the removal tool and follow the instructions:
http://www.avast.com/uninstall-utility

Poof, internet connection restored!

At this point you have to decide whether to stay with avast or not. This was a darned annoying problem, but otherwise I’ve had years of troublefree service from avast so I decided to reinstall. Just download the avast installer and install fresh. This worked and I’m up and running again, but something that made me unhappy with the reinstallation is that despite selecting the custom installation option, without asking me the installer:

  • Installed Google Chrome (not terrible, but I don’t need yet another browser).
  • Made Google Chrome my default browser (definitely not cool, avast).

I hope this helps you, ratpit, and any others who have this problem.