crashing, can't kill debug EXE in Task Manager

[ElectroLund]

I have a CVI application that I'm debugging.  The project uses a DLL that I created with CVI.  This DLL has been stable and "working" for some time now.

But now, I'm seeing odd behavior.  As I'm debugging my main application (which has the DLL attached), some calls to DLL functions are failing to finish.

When I stop the debugger, CVI hangs hard.  It doesn't recover, I have to force close CVI.EXE (this works).  But my debug app EXE remains in the process list.  I can't kill this by any means.

Why is my DLL so unstable now?  The function in question should return a status code.  

[samazing]

It may be hard to pin point why your custom DLL is behaving unexpectedly now. When you put quotes around that the DLL was "working", what do you mean? What is your DLL attempting to do when it hangs/doesn't finish?

Could you post the status code that the function returns?

[ElectroLund]

Thanks.  The DLL does a bunch of RS-232 Library calls (mostly ComRd and ComWrt), packet assembly and binary parsing for a custom protocol. 

By "working", I simply mean that the above usually works as designed.  Return codes are pretty simple too: 0 = good, -1 = bad.

Now for what it's worth, after several reboots yesterday, I haven't seen this hard crash.  I don't know!

This isn't the first time I've had very unexpected behavior with the debugger.