iCloud For windows 11 does not sync and appears to stall at log in

After hours of trying to get iCloud to complete the sync of Files, Photos, and Passwords, etc. I was able to figure out the root cause with some assistance from Apple Support.

YOU MUST SIGN IN WITH YOUR ORIGINAL APPLEID!

Scenario:

After installing iCloud for windows and completing initial login and setup, the application seems to get stuck. No sync will happen and quite frequently it will hang on the login screen when you reboot after the initial setup. This was especially hard to troubleshoot because the application throws no errors so it is difficult to know what to chase down.

Root cause:

I typically use my iCloud email address whenever I log into apple services and that normally always works, but for some reason the iCloud sync will not work if that email address is not the original AppleID. My original AppleID is an "@gmail.com" address. Once I logged into the iCloud for Windows app with my original AppleID, the application lit up and started working.

I would suggest that Apple Engineering account for this flaw somehow and either fix the login issue or create an error message stating the original AppleID must be used to log in.

Shout out the two individuals that assisted from Apple Support.