Solved! iCloud on Windows 10 Settings window is blank

I had the problem discussed here:

https://discussions.apple.com/thread/250093779?login=true

and I was able to solve it.

I had disabled Windows built-in ZIP file support for other reasons and that seems to bother iCloud severely. If you're not sure if this might be your issue just copy/paste these four lines into a text file and give it a name with a .REG extension. The run the file (or have the Registry Editor read it for you).

Either this will work or not, but after this the Windows setting will be set to the correct default installed value.

[HKEY_CLASSES_ROOT\CompressedFolder\CLSID]

@="{E88DCCE0-B7B3-11d1-A9F0-00AA0060FA31}"

[HKEY_CLASSES_ROOT\SystemFileAssociations\.zip\CLSID]

@="{E88DCCE0-B7B3-11d1-A9F0-00AA0060FA31}"

I hope this helps someone.

I would suggest to the Apple Development team that you check for this registry key.