Driver suddenly became unsigned

I noticed my Xbox One wireless controller no longer worked in Windows 7. Under Device Manager, it said:

Windows did not start a related device driver. To learn more, click the Driver tab and then click Driver Details.

Previously I had errors about drivers that weren’t signed.

It shows up under the Windows game controllers setup, but Steam won’t detect it. I assume this is some sort of security precaution against cheats or something.

I ran sigverif.exe and the matching driver is C:\Windows\System32\drivers\WdfCoInstaller01011.dll. It’s dated 2015 and matches the one in the Xbox One driver download I found (with considerable effort). If I restart my computer and disable driver signature enforcement then everything works fine.

I’m stumped how to get a working version of that dll into the drivers folder.