Just an FYI, if you go ahead and "clean" the WIndows installer issue with the problem named "C:\Windows\Installer\_{ECE5B218-A086-4E18-A362-D11181681457}\OlderProductDrivers" you will never be able to install any Intel wifi driver (see attached screenshot). You will also not be able to uninstall an older Intel wifi driver.
That directory that CCLeanner wants to empty is critical to Intel wifi drivers...
CCleaner needs to be more careful what it marks as removable, as I just went through two days of hell trying to recover my wifi drivers from that cleaning.
For the first time ever I am now afraid of CCleaner, and I have been a paid customer for quite a while.
You have been on the wrong end of the stick with the outcome, and very reason why, Registry cleaning should be avoided all together or at the very most, only used when all other avenues have been exhausted.
In other words, reg cleaning should not be a routine housekeeping chore, it is a problem solving tool when trying to fix some issue with your PC.
The chances of being adversely effected are far greater than any advertised benefits.
And for all those who say they have never been effected, I simply add to that statement:- "Yet!" or "That you know of".
I take it by your 2 days of hell that you didn't do the reg backup offered?
Hopefully your experience will be a cautionary tale for others if trying to swim the dark waters of registry tweaking.
Do you remember where you saved the .reg file backup, just curious because the default location (Documents folder from memory) should not have been affected by System Restore points.
And despite the circumstances, welcome to the forums.