For a properly functioning computer system remove Avast from the system with an uninstall utility. A uninstall utility is available for free download from the internet. To uninstall Avast completely,first disable Avast's self protection. It is recommended to restart the Windows PC in safe mode and then run the downloaded utility. Once Avast has been removed from the computer system, it becomes vulnerable to viruses,malware and spyware. To uninstall Avast completely, restart the computer system in the normal mode once the uninstaller has finished removing Avast. For data security purposes, a new anti-virus must be installed soon.
To completely uninstall Avast! Free Antivirus (or Avast! Pro), simply use the uninstall utility.