I have software-only device driver I compiled from the Windows WDK samples (simgpio.sys). How do I install this? All the instructions I've found are for hardware drivers.
UPDATE 7/2/20
I made partial progress. If I Ctrl-RtClick on the INF file, there is a menu item "Install". This seems to work: "The operation completed successfully". It still doesn't show up in DeviceManager, maybe because it has no associated hardware (?)..