Error while opening sound device

For some unknown reason, my Audacity 2.0.6, quit working today. Using Windows 10. When I go to Edit>Preferences>Devices, I have MME selected for Interface, under Playback / Device: Speakers, but under Recording / Device it says NO Devices Found, and the dropdown arrow says the same thing. Any advice as to how I fix this or where to begin?

The first that comes to mind is Clean Restart Windows.

Shift > Shutdown. Start. That cleans out the most existing Windows activities. Just because you shut Windows down normally doens’t mean Windows forgot where it was or what it was doing.

Make sure all your devices and hardware are connected and working before you start Audacity.

If you get the service to come back, you might consider upgrading to Audacity 2.2.0.