Hello Excel,
I have now returned from my business trip, and have managed to update my computer. I tried your suggestion, but it did not work - when I re-tried here in UK I used the Microsoft link - which at first did not improve things, but persistence paid off, and it worked.
The only significant hardware difference was that instead of using a 128GB SD card as the additional storage, I used a 16Gb USB memory stick. I have no idea why that should have made a difference.
I believe that Microsoft also made some changes to the update process on 15^th^ May – it could be that was the change that made it happen.
The update process was very, very slow – several hours.
Thanks for your suggestion and the offer of help.
John PINK