I left a couple months (most recent) of folders in there and deleted ~18GB.
All good so far.
Will delete the rest after a few days without incident.
My next question will be why are these folders...

FYI, I'm in the process of deleting now. Will post back how it goes...
Thanks all.

Thanks Layback Bear. I'm not going to delete TrustedInstaller just the folders in cbstemp.
Do you know of a problem if I do this?

Thanks all for your responses.

I have tried the built-in disk cleaner and CCleaner, but neither of them removed these files/folders.

It's interesting that I can't find any information about...

Helping my dad out. He has Win 10 laptop with only 1GB free on a 56GB drive. Ran TreeSize and it shows 25GB are in the CbsTemp folder (c:\windows\CbsTemp).

There are hundreds of folders inside...