Upgraded to Windows 10, can't delete 8.1

[AGnu]

My laptop keeps telling me I need to free up space but every time I try & run the "clear disk space" thing that it tells me to do I get most of the way through the process & then when it's supposed to be deleting old installations the box just closes & when I go back into it nothing's changed.

Any ideas? My poor laptop is now apparently completely full & I can't do anything about it! It was showing as less than 50% before all this!

Have you tried turning it off and then on again and trying again? Sounds stupid but fixed most of the problems my mum had with windows 10.

Also, sounds like you have done this from what you have said so far, but make sure in the disk cleanup bit you've clicked on Clean Up System Files and then there should be a tick box for previous windows installations. Make sure that's ticked when you start the clean up.

I'm hanging onto mine for now, even though it's taking up an extra 16Gb or so, just until I know I'm completely happy with 10.

Yes, I've been trying for days - I was determined I could fix it all by myself...

I've just reverted back from windows 10 to windows 7 so I'd warn against deleting it too soon.

Try this: www.theguardian.com/technology/askjack/2015/aug/27/microsoft-windows-10-free-upgrade-revisited-questions-answered - it has instructions on how to roll back the install, but also tells you where the old system files are so you could maybe delete or move them off to an external hard drive.