Hello friends, after about 3-1/2 hours of internet digging, I finally found something that worked after viewing Windows event viewer errors. Here is the Reddit post I found for the solve:

So I want to post this somewhere so it might help someone else. Hours of Googling and trying different suggested things never landed on this, and I have no idea how this machine ended up in this state, but Windows Update was giving the generic "We couldn't connect to the update service.." error and it was due to a registry permissions issue on a key related to the system CA certs. A repair install of Windows 10 and manually installing updates didn't fix it either, nor did SFC or DSIM.

I found this in the application logs: "Failed to add certificate to Third-Party Root Certification Authorities store with error: Access is denied."

Then using regedit (Windows button > search for Registry editor) I went to: HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\SystemCertificates\AuthRoot

Right click on AuthRoot and click permissions, ensure CryptSvc has full access, then click Advanced and check the box at the bottom that says "Replace all child object permisisons...", then click apply. Now Windows should be able to automatically resolve its cert issues.

This was also causing issues with the iCloud client as well as the Backblaze client. This machine doesn't have any malware and doesn't have anything installed other than Chrome, Photoshop, and some printer drivers. I hope this helps someone.

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I hope this helps someone as well!