I'm having a problem running Sonar X2 Producer. It starts up fine each day. However, after shutting it down the first time, it will not restart. When I open the Task Manager, I see that "SONARPDR.exe" is one of the processes that is still running. If I shut it down in Task Manager, X2 will restart. My question is, is this a bug in the program, or is there a setting/plugin/driver/what-have-you that will cause this?

What do you have hooked up to your PC that is used in Sonar? An example would be any USB or Fire-wire hardware, like a MIDI controller. sometimes these things can cause Sonar to hang as the controller doesn't let go of it.

You using any M-Audio gear? Lots of complaints about this. Only solution seems to be what you are already doing (ending the process in the Task Manager).

Thanks CJ and Beepster.  No joy here.  I don't have any external hardware hooked up specifically for Sonar.  The only things I have are a wireless mouse/keyboard combo and a couple of flash drives that have no files or anything related to Sonar on them.

hmm... weird. Have you installed the quick fix? I'd also check to see if maybe there is a driver update for the keyboard/mouse as well as any other hardware. Is this a new computer? Cheers.

What are you using as an audio interface (sound card)? 

Oh, Dave!  I was hoping nobody was going to ask me that question and show that the emperor has no clothes .  I have only onboard sound   I used to have a nice computer with a quad-core CPU, not great but nice sound card, and a Raptor drive to make real fast, but it crapped out on me a couple of months ago, and I haven't had the money to replace it.  I had to buy a work computer, but I have gone as long as I can stand without Sonar, so I'm basically running it on a glorified electric typewriter  

If you google sonarpdr.exe you will see that it's a well known issue. It seems to be related to soundcard drivers although i havent come across a definitive explanation.... maybe there isnt one! 
I had a delta1010 and sometimes it would happen, and I now have an octa capture and it has happened but very rarely. Since win 8 was installed it hasn't happened at all. Could be coincidence! 

Bibs

Yeah... not to be "that guy" but you need an interface. It's likely the soundcard not letting go. You're just gonna have to use End Task for now. Really if that's the only issue you are having that's pretty minor as far as annoyances considering. 

I'd still check for any fresh drivers for it and whatever else you got going on. Optimize the system for audio and find out what the preferred driver mode of the card is.

Also you might want to keep a wired mouse and keyboard handy. Those wireless set ups can cause stupidness as well with their drivers and whatnot. It's just an extra little thing to try out when troubleshooting.

Cheers.

Sometimes you can't even end task no matter how many times you click it or however long you wait and as a result a reboot is the only option. Real pain in the proverbials!

Bibs