The "class not registered" error typically indicates that there is a problem with the registration of a component or application, which can often be caused by a corrupted file. In your case, since you mentioned that explorer.exe is not loading properly, it is likely that the issue is related to a corrupted installation of Windows or the Explorer application itself.
To resolve this issue, you may need to reinstall Visual Studio if it is related to your development environment, or consider repairing or reinstalling Windows if the issue persists with the explorer.exe functionality.
Additionally, if you are encountering this error while trying to connect to a remote computer, ensure that the user profile is not mandatory, as this can also cause the "class not registered" error.
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