Hope I'm not overlooking a redundant post..
When I close MC7, I cannot reopen until I go to Windows TaskManager and end the CWMC.EXE process that appears active since the previous session. This behavior seems to be independent of launching with the EXE, a shortcut or from the command center. I'm experimenting with numerous VSTI synths, so I can't rule out this might be the hang-up source, but I'm wondering if anyone has experienced this?
Win7 x86 Enterprise
MC7 v21.0.1.34

I know of two ways this happens:
1) sometimes 32bit plug-ins have trouble shutting down keeping 64bit DAWs open and
2) sometimes a DAW is waiting on a reply from an interface driver.
Since it appears you are running a 32bit OS, it would rule out #1.

Thanks Scook,
I'm investigating further here and I think it may well have to do with VSTI synths locking up the process of the main app..  it also could be a problem with my onboard soundcard utilizing ASIO - I'm seeing occasional conflicts with my browser sharing the card (using MME?).
Any additional input would be helpful as I struggle on here, I'll post my new findings.

Indeed, if I use ASIO drivers, that's when it hangs up!
If I switch to MME (essentially making VSTI recording useless), then the process ends when I close the GUI.

Appreciate any assistance.
 

Does the chip actually have an ASIO driver or are you using ASIO4All? ASIO4All is not a proper driver, it is a wrapper which presents another driver to the host as ASIO. The best solution is purchase an audio interface designed for DAW use.

Actually, thanks Scook,
Of course, I had forgotten to mention I'm using ASIO4ALL with my onboard card.. my bad!
That must be the source of the issue.  I'll try with another native ASIO supporting device and report back!

You might also try NOT having your Windows Default Audio Device set to the same device Sonar is pointing at (ASIO4ALL).
 
Bob Bone