This is the new link to remove ALL versions and products of Avast:
http://files.avast.com/files/eng/aswclear6.exe.
The problem is that when you have multiple versions in your machine, when you go into Safe Mode to use the Uninstaller Tool,
you can only uninstall one version at a time, then need to reboot. Then you need to go back in and do it again for a different version...at least this is my experience using XP-Home, XP-Pro, and Vista machines.
To remove all versions (4.0, 5.0, 6.0, etc.) from your machine:
1. Save a copy of Avast (the version and product you need) and save it to your HDD:
http://www.avast.com/download-software – all products – 6.0.1091
2. Download the Avast Uninstall Utility
http://files.avast.com/files/eng/aswclear6.exe and save it to your HDD.
3. Disconnect from the Internet at this time.
4. Go to Control Panel and uninstall Avast through Add/Remove Programs if possible and reboot.
5. If Step 4 fails, boot into
Safe Mode (hit F8 repeatedly) and run the Avast Uninstall Tool.
6.
Reboot. If you have CCleaner on your machine, run it now to clean up your machine.
7. Install the newest version of Avast and
reboot.
8. Get Internet access and register your copy or add the license key for Free, Pro, or AIS.
Free –
http://www.avast.com/registration-free-antivirus.php9. Update the Avast definitions.
Let us know if this fixes your problems. Thank you.