I had upgraded to Windows 10 on two desk top and one laptop computer during the free upgrade period.
All was well with one desktop and the laptop, but I was continually having problems with the other desktop.
I had the Installation Program for Windows 7 on a flash drive, so I re-installed Windows 7. It is working well, no problems.
I however observe two VERY LARGE Files: windows.old and windows.old.000 that appeared on my C: Drive after the re-installation procedure. If I recall correctly, the file windows.old appeared after the upgrade to Windows 10 and the file windows.old.000 appeared after the re-install of Windows 7.
I assume these two files are for returning to the previous operating system. There is no way I would want to return to Windows 10 on this machine, so may I delete these two files?