I use PowerRun from sordum.org to launch a 3rd party File Manager app like Explorer++ or Winfile from Github (or maybe Unlocker) to remove the windows.old folder as a last resort.
if not, some other 3rd party app or driver is locking up that folder (can't say which one), which needs to be removed first
Alternatively boot your PC from a live Linux release, either USB or DVD. Don't install Linux just run it from your chosen media. When in Linux browse your C: drive and find Windows.old then delete it. After doing this make sure you empty Trash in Linux. If you don't empty Trash in Linux it will leave a Trash directory in Windows.
If anyone takes this adventure and it fails up, after your get your computer up and running again, do report it here just for curiosity sake.
If mucking around causes problems, maybe it's time to stop mucking around? Just leave Windows.old alone.
It's just one more folder (among 100,000 others) that we don't need to know about, don't need to care about, don't need to do anything about.
Don't worry. Be happy. :)
I've taken your advice a couple years back Mulgrave. Thank you for reiterating that advice!
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