Avast 8 antivirus not compatible with Windows 8 pro. Avast's latest antivirus version 8 is not compatible with Windows 8 pro. I installed twice and forced to uninstall it from win 8 pro after compatibility issues. Avast ver. 8 killing Task manager after installation. It does not allowing to run task manager. Also sometimes blank screen apears after log in. there is no chance of infected setup of Avast antivirus because I downloaded it from official website of Avast. So this is clearly compatibility issue. Anyone using windows 8 pro here?