Becuz of bunch of bugs, I need to go back to 8.
But I cant find anything in official site

Download old free versions from FileHippo as for the Internet security version I don’t know.

You can go back to Avast 8.0.1497 but I’d rather want the issue to be resolved…

I can’t find a link to the Internet Security BUT once you’ve installed the free version, set the update to manual (see note) and double click your license file it should auto upgrade to Internet security.

Anyways…

  1. Download the right aswclear and the appropriate program

Avast 8.0.1497 : http://www.filehippo.com/download_avast_antivirus/download/0c203d8e8244458c5da81998eb76f523/

v8 and below : http://www.avast.com/uninstall-utility
v9: http://files.avast.com/iavs9x/avastclear.exe

  1. Uninstall Avast by control panel [If you don’t have Avast in control Panel go to #4]
  2. Uninstall in safe mode using aswclear (v8 or below) or avastclear (v9) [If you don’t have Avast in control Panel just install it]
  3. Download and install your version
  4. Reboot.

Note : Once installed make sure you change program update TO MANUAL.