Re: [pyusb-users] No Backend Available

[Xiaofan C. <xia...@gm...>]

On Thu, Jan 21, 2021 at 8:44 AM Jonas Malaco via pyusb-users
<pyu...@li...> wrote:
> > According to Process Explorer, there is now an QueryNameInformationFile for:
> >
> > C:\Windows\System32\libusb-1.0.dll  (because the program explicitly
> > looks for it there!)
> >
> > in addition to accessing libusb-1.0.dll in the 'library install' directory.
> >
> > Perhaps I had the wrong version of the library somewhere?
>
> Yes, that was probably it.
>
> I'm not super familiar with how DLLs are loaded by Python on Windows, but it's
> possible that if a DLL is found with the correct *name* the search stops, even
> if later the DLL turns out to have been built for the wrong architecture.
>

This DLL search order is from Microsoft.
https://docs.microsoft.com/en-us/windows/win32/dlls/dynamic-link-library-search-order

You can see it is pretty complicated.

So the best way for end user is to remove libusb-1.0.dll in all the
directories except
the system directories. If you use Zadig to install WinUSB driver,
that is automatically
done.

-- 
Xiaofan