Re:SONAR won't recognize my sound card as a valid output
First thought that comes to mind is the fact that midi outs are actual physical midi ports unto which you can connect external midi devices.
Does your (name unmentioned) have actual midi ports? Either ins or outs?
Next thought is that since midi ports are not audio outs, you should be looking under audio options (not midi devices) if you are trying to get audio running. Go there and make sure you have selected available audio drivers and that you have selected the proper type of driver (ASIO, WDM, MME) for your (name unmentioned) soundcard.
Core i5 Windows 8.1 64 bit 8 Gigs RAM
Sonar X3c Producer M-Audio Fast Track Ultra 6.1.9