While installing or running programs on your computer, the chances are very good you will have encountered a window that pops up telling you “This program might not have installed correctly“. There was a new feature introduced in Windows Vista and 7 which is supposed to actively monitor and detect the known compatibility issues with older programs when you try and run or install them. If it detects any potential issues, it will throw up the not installed correctly window. You will then have a choice whether to try to reinstall with the recommended settings, which is usually detecting issues with User Account Control or trying to run the program as an earlier version of Windows in compatibility mode. Or you can simply tell it there was no problem and carry on.

That’s the theory anyway. Unfortunately, the Program Compatibility Assistant is far from perfect, and quite often will show the window when there have been no issues at all with the program or installer. Even worse, this window will also be triggered by a lot of portable software, or even when you simply cancel an install process. If you are someone that likes to try out a lot of different software, or use a number of portable programs, this window showing up so often can be quite irritating.

Thankfully, there is a simply way to disable this as the ‘Program Compatibility Assistant (PCA)’ is nothing more than a Windows service that can be manipulated like any other. Type ‘services.msc’ into the search box in the start menu, or open the Task Manager, go to the Services tab and click the ‘Services’ button. Look for the ‘Program Compatibility Assistant Service’ and right click on it.

Select ‘Properties’ and change the ‘Startup type’ in the dropdown box to Disabled, and then apply it. The Assistant will now be disabled and no more popup windows will appear.

Do be aware that on occasion the Program Compatibility Assistant can sometimes completely block a program from running because it has detected more severe issues than those which would trigger the simple “This program might not have installed correctly“ window. If you have turned PCA off, this software will now run and could cause issues with the system if there really are serious compatibility problems with it. It is probably not advisable to turn off the Compatibility Assistant if you are not experienced enough to know when there is likely to be an issue with a piece of software, or you use a lot a lot of older software.