Programs won't run any more.

[Fried laptop]

Today I've installed Ccleaner and used it, for the first time on this machine. Using the free premium trail I've ran the cleaner, health checkup and registry fixing capabilities. Now I can no longer use programs like firefox, windows media player, groove music or skype. Youtube, when opened with Windows Edge, does not play any videos. Almost all the programs the computer was used for are now out of commision.

The OS used is Windows 10 Home

What can be done to fix this horrid mess?

Edited March 26, 2022 by Fried laptop

[Nergal]

When you did the registry section i assume you just blindly cleaned everything that it flagged,  this was a mistake if you did (best practices can be read in my signature below). Did you make a backup when ccleaner prompted you (during the registry section).?

[Fried laptop]

Yes, I did opt to have registry backed up when prompted. Unfortunately, I can't use it to restore the registry. The error message says: not all data was successfully saved in the registry. Some of the entries are being used by the system or other programs, or you do not possess privileges necessary for this operation.

Edited March 27, 2022 by Fried laptop

[Bastet]

If you have an image backup then restore it.
If you don’t then try system restore. If this doesn’t work then you’re looking at a clean install of Windows.