Don't know what the error is, but it looks like something in the registry is causing it. I renamed HKEY_USERS/<whatever>/Software/Paint.NET to HKEY_USERS/<whatever>/Software/Paint.NET.old and that fixed the problem. You will lose your file history in Paint.NET and possibly other defaults and settings, but it will at least get you back up and running again.
installation error
in Troubleshooting & Bug Reports
Posted
Don't know what the error is, but it looks like something in the registry is causing it. I renamed HKEY_USERS/<whatever>/Software/Paint.NET to HKEY_USERS/<whatever>/Software/Paint.NET.old and that fixed the problem. You will lose your file history in Paint.NET and possibly other defaults and settings, but it will at least get you back up and running again.
HTH,
rgds
Dave