Premiere won't shut down

Whenever I close Premiere Pro CS6 on my Win7 box, it saves my project and shuts down.  However, attempts to run it again fail.

I learned the reason why... it had never really shut down to begin with.  Opening up Windows Task Manager shows it still running in the Process tab.  If I right-click and choose "End Process" it will then shut down so I can open up a new instance of the program.

Anybody know what the problem could be?  My other Creative Cloud apps do shut down correctly.

Thanks,

Rick