Windows.old? Can I delete it, and how?


Sep 12, 2012
So, I had a copy of windows installed on this somewhat old HDD and, since my SDD didn't have enough space for me, I plugged in the old HDD.

Now, I don't know if it's safe to delete everything on the HDD (I don't need anything on it, I need the space), so I tried to, and it wouldn't let me. It said I needed permission from SYSTEM (what?).

Also, windows keeps reporting that the HDD is in danger of failing and me losing files. Could this be solved by deleting all the files on it or is it more likely some other problem that will probably make it a bad idea to use it in the first place?

If you can answer any of the questions I'd be more than grateful, thanks for reading :).


Dec 30, 2012
From my experience, Windows.old contains files left over from your previous OS. When I upgraded from XP to 7, I had a windows.old folder that just had some junk from the old OS on it. It's probably safe to delete, but I would browse through it to be sure nothing important is in it.

I don't believe that the HDD failing has anything to do with the mystery folder. So, you probably shouldn't use it.
Just re-format the drive, that will delete everything on it.

The drive failing has nothing to do with the file, the hard drive is old so it can be expected to fail eventually.
So don't put anything important on it (programs) and try to use it sparingly. My secondary storage drive is pretty old and has reached its bad sector count so it has technically failed, but it still works fine. But I have backed up everything on it though, be prepared that the drive will just fail eventually.