Q: How can I test that Microsoft .NET Framework is working correctly on my computer?
A:
If the test above shows that Framework is installed, but QuakeMap doesn't start - please test your machine with
a couple of simple programs here (a zipped file 7Kb with two .exe files packed inside, unpack and run each of them).
You should see something like this:

Please make a note of the version numbers you see and report the problem to QuakeMap support support@quakemap.com.
Here is a link to Microsoft article about uninstalling and repairing .NET Framework