Virtual Box refuses starting with E_NOINTERFACE (0x80004002) on Windows 7

I had an Virtual Box installation I haven't used for a couple of months (so I don't know exactly when the error occured) but was running back then.

Now I tried to start Virtual Box but on the startup all I get is an error prompt:

Virtual Box - Critical Error

Failed to aquire the VirtualBox COM object.

The application will now terminate.

Details:
Failed to instantiate CLSID_VirtualBox w/ IVirtualBox, but CLSID_VirtualBox w/ IUnknown works.
PSDispatch looks fine. Weird.

Error code: E_NOINTERFACE (0x80004002)

Component: VirtualBoxClientWrap

Interface: IVirtualBoxClient {d2937a8e-cb8d-4382-90ba-b7da78a74573}

I already tried deinstalling Virtual Box completly and reinstall the newest release (VirtualBox 6.0.10 132072 Win). But the error still occurs.

I am on Windows 7 Enterprise with Service Pack 1.

Anyone else experiencing this and knows how to fix this? My google search wasn't very helpfull.

Found this link.

It still can be fixed by editing registry entries (editing from filename to full Windows/System32/ path):

HKEY_CLASSES_ROOT\CLSID\{00020420-0000-0000-C000-000000000046}\InprocServer32\InprocServer32

HKEY_CLASSES_ROOT\CLSID\{00020424-0000-0000-C000-000000000046}\InprocServer32\InprocServer32 

Does anyone understandy why this occurs?