Windows 10: Upload file for iCloud photos is missing

After installing Win 10, my HP desktop has a fit at startup. Message slides rapidly in and out, saying 'Upload file for iCloud is missing' . Screen alternates with black screen several times. Tool bar disappears and re-appears a few times. Eventually, about 5 minutes or so, and after CPU fan has made a lot of noise, everything settles down and PC behaves normally.

:)

 

How do I stop this annoying message Upload folder for ICloud Photos is missing from continuing?

How do I stop this annoying message Upload folder for ICloud Photos is missing from continuing to overload my messages?

 

WIndows 10 and iCloud

Windows 10 loaded fine on my desktop PC, but as soon as I restarted, the iCloud icon popped up with an error message 'My Photo Stream can't be updated because you don't have permission to add files to the download folder.' The whole system became de-stabilised
but I managed to revert back to Windows 7, where the following message appeared in the task bar on the iCloud icon: 'The upload folder for iCloud photos is missing. The upload folder for iCloud photos has been moved or deleted'. So, I deleted iCloud, re-installed
it, and loaded Windows 10 again. As soon as I had loaded Windows 10 again and restarted, the same thing happened. I then managed to get into settings in Windows 10 (although this was difficult because of the de-stabilisation) and deleted iCloud, whereupon
everything worked fine. Oddly, I have iCloud on my Laptop and there have been no problems with the Windows 10 upgrade. Any advice or ideas to overcome this would be appreciated (of course I don't now have access to my iCloud contacts list in Outlook!)

Thank You!