Windows 10 20H2 update broke registry access for my application.

Since the release of Windows 10 20H2, I have been getting multiple reports of users having issues where my Win32 app's settings in the windows registry are not saved.

Using a debug version, I figured out that calls to WinAPI's "RegCreateKeyEx" and "RegOpenKeyEx" return an 0x00000005 error (ACCESS DENIED), even though this is the public registry (HKEY_CURRENT_USER) and this access worked without issues for over 20 years.

I was not able to replicate this issue on my development PCs, which means that this issue may have something to do with some 3rd party program (maybe an anti-virus that got messed up by the 20H2 update).

Has anyone else encountered anything like this after the Win10 20H2 update?