Checking storage space

[dwdraw2]

Yesterday, I mysteriously lost 20 gigs of free space? It was always around 143 gigs of free space, but today it's at 123 gigs of free space. Is there a way that I can find out at what is occupying this space? And, or could this be the disk itself failing?

Thanks for your time.

dwdraw2

 

[Bighorn]

In File Explorer and the C: drive, do you show a Windows.old Folder? If so check the size. I usually wait 10 to 14 days then use Disk Cleanup, usually gets rid of that Folder.

 

[Saltgrass]

You could also go to Settings-System-storage and select the partition you want to check. Maybe you would notice something.