I had to reinstall Platinum.   Now that everything is installed again, there's no sound.  I inserted Toontrack drums and EZkeys, but they don't play.   My MIDI keyboard isn't getting any sound.  The meter does move, though, when I playback both drums and keys.   So I know sound is getting through, just not through my monitors.    I know my interface drivers are installed properly.    I tried to reconfigure my MIDI setup within Sonar, but that didn't work (probably lack of knowing what I was doing).
 
Any help would be appreciated.
 
Thanks,
Greg
 

Have you restarted your computer?
Echo/monitor buttons are pressed down on the track?
Are tracks going to the master bus?
Have you checked the master bus output?

I have restarted the computer.  I will check the others and see.  
 
Thanks!
Greg

After a fresh install I have a routine which involves a few minutes going though all the tabs in Preference to look and make sure your settings are all correct. 
Make sure your using the Focusrite ASIO driver and all the in/outs are checked.  
Make sure you keyboard controller is set up in Midi Devices. 
To test sound insert a VST that has a GUI interface you can "play" like Lounge Lizard or EZ keys and play it.  
If your not getting sound from the GUI then you need to check your output routing is set correctly. 
 
Are you getting direct sound from your interface to your monitors if you plug a guitar or mike in? 

I think I found the issue.  In Devices I checked the Use Friendly Names for devices.   Everything works now.
 
Thanks for your support!
Greg