Event Trace question

I have an event raised when a delivery document is saved. It should be triggering a terminating event for my task, but when I look in the event trace, I see the message in the Receiver Data area:

Address doesn't exist 9000000625

and in the Trace Data area:

"Event entered in event queue".

So it seems there is something wrong here, but I am not sure what it is. Looks like my event isn't finding it's object, could that be it?