I have a midi (.mid) file on my computer. It plays perfectly in Windows media player. However, it doesn't play in Sonar. All the lights light up and bounce around, as though it is playing, but nothing comes out of the speakers. I have used DAW software in Linux, but I have zero experience with Sonar. Any suggestions?

Hello and welcome.
Would it be possible to update your footer like mine so we know about your system and software.
So does Sonar plays audio other than midi? You have a soft synth assigned to midi? You are using X2A?

I am not sure how to update my footer. I have Windows 7 Home Premium 32-bit, and an on-board sound card that I can't identify but that Sonar recognizes as simply: "High Definition Audio Device". Sonar can play .wav files. I am not using SoftSynth (at least not on purpose - it is a fresh install of Sonar). Midi files will not produce audio in Sonar, even though other programs can play midi files just fine.

https://www.youtube.com/watch?v=KiWhUAWJ6ZI&feature=youtube_gdata_player
 
Also please insert a soft synth track and drag your midi into that. F1 will access online help if you need to know how to do this.
 
To be honest you will probably need a dedicated audio interface that handles ASIO. Your internal sound chip will not be up to much performance wise.

I watched the tutorial. There are no MIDI devices listed in Sonar when I go to edit/preferences/midi/devices. So I guess I am out of luck. But, that begs the obvious question: if I don't have any MIDI devices on my computer, how is Windows Media Player playing MIDI files? Windows believes I have a MIDI device....

You should have Microsoft GS wavetable synth as shown in vid.
Try the softsynth step I wrote earlier anyway. If you are playing wavs that should work anyway.
 
Cheers.

Oh and make sure there is a sound preset applied to that softsynth such as 'piano' or something. Cheers.

tomvalois
I am not sure how to update my footer.

User Control Panel > Edit Profile > Signature and Comment

tomvalois
I am not sure how to update my footer.

Go into User Control Panel at the very top of the screen.
Then Edit Profile > Signature & Comment
 
Please list everything about your system - make/model etc, CPU/RAM/Hard drives etc
Also, which version of Sonar are you running?
All version come bundled with at least SOME instruments, you simply get more as you go up through the versions
 
Please also note that Midi by itself is just data - it's not audio so you won't get any sound out of it until you've connected it to a soft synth (vsti)
 
 

Your safest bet to play a midi file as a beginner is the tts-1. It is multitimbral so will catch all the instruments in the file. If you insert that synth as a simple instrument and then drag the midi file on to that track it should work.