Recently the XP AntiMalware virus -- or some variant -- knocked out the ability to run certain EXE files. This was very frustrating because I was not able to run my standard set of antivirus / antimalware programs.
When I clicked on the program icon, it would ask what file I wanted to use to run the program. The "trick" that the virus used was to redefined how EXE files are run.
You have to go into the registry to fix this problem.
Run regedit and navigate to HKEY_CLASSES_ROOT\.exe. The value should be exefile. In my case, the virus changed this value to secfile. After resetting it back to exefile I was able to run EXE file.
In order to remove the rest of the XP AntiMalware virus, I did a search in the registry and removed all instances of secfile, VMA.EXE and AVE.EXE.
A final run of Malwarebytes AntiMalware removed the rest of the infestation.
More information on how to fix this problem can be found at this link: