Last week while teaching the BizTalk Developer Immersion, I was demoing how to resume suspended messages using the BizTalk Group Hub. I submitted six messages while my send port was stopped, so all the messages were suspended. I was foolishly trying to show my students that if I resumed the message, it wouldn’t be processed because the send port was in a stopped state. I resumed the message and it disappeared, actually, it went out through the send port. This confused me, I had six suspended messages, I resumed one and it was processed so I only had five. But why? I couldn’t figure it out, the port is stopped, the message shouldn’t be processed but if one went through why not all of them. I was stumped, then it occurred to me. If I were in production there are dozens of scenarios where I could have dozens or hundreds of messages in the MessageBox waiting for my send port to start, but before I actually start it all up, I want to send a few specific messages as a test. By stopping the port I can see all the messages that the port subscribes to and choose which ones should go through. So now I think it’s pretty cool.