Sometimes, it becomes very difficult to uninstall antivirus software completely from our PC. The default uninstaller packed with it is either broken and thus non-functional, or that it leaves traces behind that prevent the installation of an update, other version or third party product on the system.
The majority of companies that produce security software for Windows make available removal tools that delete all traces of a product from a system. These tools use hard coded lists of files and locations usually and are considered thorough because of it. Sometimes, they combine the list with searches to make sure that all program files and Registry information are removed from a computer system.
The Avast! Cleanup Tool is a third party program that is not to be confused with the company’s official removal program Avast! Uninstall Tool.
To completely uninstall a supported version of Avast, simply run the tool after you have downloaded it to your system. First screen displays information about the program and its intended uses. Once you click on accept, you will notice that two command line prompts are launched that perform the uninstallation of Avast software on the system.
Please note that the cleanup tool is only compatible with Windows Vista or newer versions of Windows, and not Windows XP.
Note: It is highly recommended to try the official Avast! Uninstall Tool first before you make use of third party software.