Hard Drive Space Technical Issue on W10- Help!

[Byrese]

I'm sure this is pretty simple. I upgraded to W10 without a problem. Going through my Windows C drive I noticed two windows folders. One says Windows and the other one says Windows.old The Windows.old folder seems to have a copy of the user and program folders that I can see elsewhere (outside of the Windows.old folder). Can I erase this? Is it truly a double? If I erase will I have a problem? See screenshot.

It's eating up 18GB

 

[pankaj981]

The Windows.Old folder has your files from the OS you upgraded from. Its mainly useful if you want to revert back to the previous version. If you are sure about not going back then yes, that folder can be deleted. But to delete it the right way, use disk cleanup and check "previous OS versions" or something similar to clean the folder