A third attempt to upgrade my desktop failed with the same unstable results given in my other thread. So I went to a backup disc that was two months old. This succeeded and I have now got a stable system however Microsoft Office Professional 2010 decided that I had a new computer and told me it was unauthorised. I could not authorise using the serial number that came with it because it told me I had already used my two allowed installations. (This desktop and a laptop). I had to use the Microsoft telephone service given in the error box to re authorise this computer. It was an automated system involving reading them a long series of numbers and them giving me one in return. This suceeded. No other problems with the upgrade so far.
Windows 10 finally succeeded in upgrading but..
