Avast Starts but doesn't update and it's impossible to uninstall via D 2 methods

My free Avast does not update. Error message ‘unsuccessful’ each time. I want to uninstall but cannot using aswclear.exe and control panel. How do I proceed?

I answered your first posts about this http://forum.avast.com/index.php?topic=96697.msg771473#msg771473.

You need to run aswclear.exe from safe mode.