What?  How?  When?  Why?  Useless?  You have no clue what I am talking about?



What are BTXTimerMessages?


They are messages BizTalk uses internally to control timers.  This includes the delay shape and scope shapes with timeouts. 



How will you see BTXTimerMessage?


You will see these messages in HAT.  They will be associated with running Orchestations.  If they show up, they will be in the Delivered, Not Consumed (zombie) message status.



When will you see BTXTimerMessages?


I see these messages when I am working with parallel actions, atomic scope, and convoys.  My sample, Limit Running Orchestrations, produces these types of message.  I have not been able to pin point the exact shapes or actions that cause these messages to show up. 



Why do you see BTXTimerMessages?


Good question.  I have a theory, but it is probably wrong.  It is that the timer message is returned to the Orchestration after if has passed the point of the delay or scope shape.  Thus, it is never consumed by the Orchestration. 



Are these messages useless?


I think so.  I always ignore them.  They will go away when the Orchestration completes or is terminated.  These do not seem to act like normal zombies in that they do not cause the Orchestration to Suspend.



Ok, so you have no idea what I am talking about?


Let me fill you in.  BTXTimerMessages in the Delivered, Not Consumed status are sometimes seen in HAT when working with Timers.  I have not really determined why they happen, but I suspect they should not show up in HAT at all.  I do not think they hurt anything and I pay little attention to them.  When the Orchestration finally ends or is terminated these messages simply go away.  They are annoying and in long running transactions can start to stack up in HAT.  Although, if you try to terminate these messages they will take down the running Orchestration with them.