Serious problem running programs, as in they simply don't work

I've installed Windows 7 Home Premium onto my computer, and after a few months or so it told me it needed to activate, and needed an activation key. I ignored it at first but then it gave me trouble. The wallpaper was always missing replaced with a black background, and as of today no program will run. I can click on anything, right-click run, all that happens is the loading circle comes up for a second and then quits. the only thing I can do is browse folders. So I activated Windows 7, but that didn't solve the problem. In safe mode I managed to run Windows Defender, after a full system scan no threats detected. I did a System restore from 2 weeks ago and that didn't fix it. So, I am at a complete loss as to what to do to fix this problem.

Extend the trial to another 30 days, then activate it
https://www.sevenforums.com/tutorials...-120-days.html

I already activated it i can't extend the time trial period. I also managed to run a "File Fixer" and that didn't to anything either.

No, i bought a retail version, but had to format my PC. Then i re-installed it. Its activated now I called the phone number and put in the code. Problem still persist.