Task Scheduler is corrupt

I upgraded to Windows 10 (on a PC), but I was unhappy with it and downgraded again to Windows 7.
After a few days I got the error 'GWXUX has stopped working'. I believe GWXUX is to do with the Win 10 upgrade. Thinking I could fix it, I tried to launch Task Scheduler.

I now get a succession of error messages along the lines of:
'Task {FD779DF0-4047-4AFF-95E5-E267E2669CB0}: The task image is corrupt or has been tampered with.'
Press OK and I get a similar message with some other entry between the {} brackets.

The computer remains usable, but I then can't get rid of the error messages or close Task Scheduler, except by re-booting.

Help to repair Task Scheduler would be appreciated.

Maybe this post will help:
My long list of Task Scheduler corrupt or tampered with tasks!!

Many thanks, UNI! Brilliant program. It repaired 41 out of 46 tasks; not sure what to do about the 5 remaining, but I can live with that.

I would run a System File Check (SFC) to see if it can find and fix issues.
SFC /SCANNOW Command - System File Checker

Racundra said:

Many thanks, UNI! Brilliant program. It repaired 41 out of 46 tasks; not sure what to do about the 5 remaining, but I can live with that.

There is info in that thread that I linked to on how to manually fix the remaining ones.

may be a system restore to a good level of previous one can regain it.then again upgrade(not sure,but a chance)