I'm hoping someone here can help me out.  For whatever reason, Sonar Professional suddenly stopped recognizing my M Track Plus interface.  It does not show up under the Audio device, and drivers preferences either.  I also tried to reset the configuration settings back to default on the off chance it might help, but as I suspected, it didn't.  Under the midi preferences it does list the M
I don't think the interfaces drivers are out of date, or corrupted because Pro Tools Express is still able to record and playback.  I don't know what else to do.  My OS is Windows 10 64 bit.  Not sure what other info would be needed.  Attached are some screen shots to give a better idea of what I'm talking about. 

I am not familiar with your interface, but all I can suggest is the you try a reboot and check your connections.  Check to see if you find your interface in Windows' Device Manager under "Audio inputs and outputs" and the "Sound, video and game controllers" options.  If you don't see it after a reboot, then you most likely have a driver problem.  Just do a reinstall of your driver(s) and try again.
 
Let us know if that works or you need further assistance.
Kind regards,
 
tecknot
I don't just work here.  I just check in once and a while.