System File Checker And Restore Errors - Game Hosed Up

Have used Windows 10 for awhile now with no problems. Yesterday, on 18 Sep I updated I Tunes. I don't know if that is linked to the problems that followed since it had been more than 24 hours since I used the PC. I tried to play Day of Defeat and it worked for awhile, but then froze up. Could not control-alt-delete and had to power down, then power back up. PC said Windows did not load correctly and do you want to try again. I said yes and Windows came up OK. Tried to play Day of Defeat again to see if the problem still existed and the game was all herky jerky and not playing correctly, but I was able to close it.

Checked around on the internet. Ran System File Checker. Came up with "could not fix corrupted file taskhostw.exe, source file in store also corrupted." Got same response to bthenum.sys. But, the last line of the SFC details said, "Verify and Repair Transaction completed. All files and registry keys listed in this transaction have been successfully repaired." So, were they fixed or not fixed? I tried to go to restore to go back to an earlier restore point, but then I got system protection error 0X8000FFFF, with most buttons grayed out. In services, microsoft software shadow copy is running on manual, task scheduler is running on auto, and volume shadow copy is running on manual. I have tried the first and last on auto, but still cant access all system restore capabilities or the scheduler to schedule restore points. I did have three restore points listed and have tried the two oldest with no improvement.

I have tried disc check and disc cleanup with no changes noted.

I have a USB recovery thumb drive and partitions on the hard drive. If used, I guess that will cause me to lose all my loaded programs, same if I "reset" the computer.

In August I added Malwarebytes to run a scan as things were acting oddly then. I guess it was Malwarebytes anti-exploit because now I can’t uninstall Malwarebytes Anti-Exploit. I get, "File “C:Program files (x86)Malwarebytes Anti-Exploitunins000.dat” does not exist. Cannot uninstall." I added malwarebytes anti malware as part of my recent efforts, but only found some PUP files. Windows defender found no viruses.

How do I get my PC to begin working properly again? Do I have to go the reset/recovery route and then rebuild everything?? Or is there a better, less terrible option?

How do I get system restore to work properly?

How do I get Day of Defeat to work properly?