- Apr 24, 2016
This test, which was commissioned by PC Magazin (Germany), looks at a rarely considered but nonetheless important aspect of computer programs: how easy is it to completely remove them from your computer? Whilst we do not encourage users to uninstall third-party antivirus programs, this could be necessary in a number of scenarios. You might want to change to a different product when your current subscription expires. Also, AV-Comparatives recommends users to try out antivirus programs using a free trial version, to check if they are suitable. Clearly, if you install a security program and then later decide that it is not for you, you want to be able to uninstall it easily and cleanly. Moreover, a standard practice if a program is malfunctioning is to uninstall and reinstall it. So, regardless of which security product you intend to use afterwards, it is important to be able to remove as much as possible of the current antivirus first.
As antivirus programs are deeply integrated into the Windows OS, uninstalling them cleanly can be quite a challenge. Furthermore, an incomplete uninstallation can potentially cause problems ranging from minor to major. You might find that you get irritating error messages, e.g. if Windows tries to start a program that is no longer installed. Additionally, there is the possibility that the “uninstalled” antivirus might waste significant disk space – up to hundreds of megabytes – by leaving numerous files behind. You might also encounter a more serious problem. For example, some antivirus programs check for the presence of competing antivirus products and refuse to install if any trace of one is found. In such cases, clean uninstallation is mission critical.
In this test, we assess how easily and completely a user can uninstall antivirus programs. We look at the uninstallation from two perspectives: first, we evaluate the usability of the uninstallation process; second, we monitor the system to determine all the leftovers (remnants of the program and its settings) remaining on disk after the uninstallation.
The test considers two different ways of uninstalling an antivirus program. The default and recommended way to do so is by navigating to Windows Settings > Apps (or Control Panel > Programs and Features), selecting the program from the list of installed apps, and clicking the Uninstall/Change/Modify option. If this standard method does not completely remove the antivirus program, many vendors offer an alternative way to remove the corrupted program. In this case, the user can run an alternative uninstaller provided by the vendor. This is a separate program, available on the respective vendor’s website, which is dedicated to removing the security product in question. It is intended to be used only if there are problems with using the standard uninstaller.
There are also other possible methods of uninstalling antivirus programs and removing their leftovers. These include third-party uninstallers (not specifically tailored to any one program) and system cleaners, and manual deletion of leftover files, registry entries, etc. We have not considered these in this test and advise readers to be very cautious about trying these methods, especially the latter. Unless you know what you are doing, you might delete the wrong thing, and end up with an unstable or even unusable PC. We also note that system-cleaning programs may promise more than they provide.
Please note that in our test, we have not considered the uninstallation of Microsoft Defender Antivirus, which is built into the Windows OS. When a third-party antivirus program is installed and registered in Windows Security, Microsoft Defender Antivirus is automatically disabled, and thus does not need to be uninstalled. Nevertheless, Defender-related files still take about 400 MB of disk space even if Defender Antivirus is deactivated.
The Uninstallation Test describes the difficulty of unistalling your antivirus is and what traces are left behind afterwards