Interface not registered error on Paint, Notepad, Outlook and crossdeviceresume.exe

Hi Andy Cannon,

Based on the symptoms and the troubleshooting already completed, this does not look like a Paint-specific issue. The key indicator is that multiple Microsoft Store/packaged applications (Paint, Notepad, Outlook, and CrossDeviceResume) are all failing with the same "Interface not registered" error on multiple Windows 11 devices.

You may try some suggestions bellow:

• Test with a New User Profile
  Create a local test account and verify whether the affected apps launch there. If they do, the problem may be isolated to the user profile rather than the operating system itself.
• Perform an In-Place Repair / Reinstall of the Current Windows Version
  Reinstall the current version of Windows following this article: Fix issues by reinstalling the current version of Windows.
• Uninstall Recent Windows Updates
  Since the issue reportedly began across multiple machines in early July, I would review installed updates and test removing the most recently installed cumulative update on an affected machine to determine whether the problem was introduced by a specific update.

If you have further information, please feel free to let me know.