MessageQueueException External Component Has Thrown an Exception

Question

Hi,

I have an application that reads messages asynchronously from MSMQ.  The application runs fine for about 12 hours or so, after which it hangs.  There are many messages on the queue and there does not appear to be a memory leak as the memory usage appears to be about the same when it's running as when it's hanging.  The application continues to request messages from MSMQ using the BeginReceive(timespan, stateobject, mycallback) method, however, "mycallback" no longer gets called.  Using WinDbg to read a dump file captured during the hang, I noticed that a MessageQueueException (external component has thrown an exception) was thrown during EndReceive.  Does anyone know what's going on or how to further debug this?  Thank you for any help.