iCloud for Windows fails to initialize

iCloud Drive is stuck "Initializing..." but no data ever syncs. iCloud Photos works fine.

I have also tried repair install, uninstall/reinstall, remove and reinstall all Apple software, reboot router, wired in addition to wireless network connection. I also tried before and after Windows 10 Update, and after several updates from Apple to iCloud. I've also tried deleting the iCloud Drive folder and allowing iCloud setup to recreate it.

iCloud works fine from a different user profile on the same PC.

Help would be appreciated.

Thanks in advance