My first attempt failed but having had a thunk and a cup of tea I realised what had caused the problem. The notes in JF's link are (to quote Eric Morcambe) "all the right notes not nessesarily in the right order". It also misses out a couple of vital reloads along the way. I've now successfully upgraded from W8 to W10 and here's how I did it.....
1. First upgrade from W8 to W8.1 and reload
2. Install all the mandatory and optional upgrades on top of W8.1 and reload.
3. You should now have a window icon in your SysTray (bottom right corner) which says
"Get Windows 10". If you have then proceed to step 4, if not seek advice from t'internet but don't go on without it.
4. Delete all files contained in the folder c:\windows\software distribution\download - there were over 17,000 in my case.
5. Got to search (top left hand corner) and enter CMD. Right click in the Command Prompt box which has just appeared. Scroll down and select the "Run as Administrator" option.
6. At the Command Prompt which appears enter "wuauclt.exe/upgradenow" (without the quotation marks)
7. Go to Settings\Control Panel\System and Security\Windows Update. You should now see Windows 10 downloading.
After it downloads and installs you will be prompted to "Continue" at the Configuration stage, this is the only interaction you will need to do. End to end it took me about 3.5 hours.
Best of Luck
