IF it's anything like outlook, the outbox is where your message goes right prior to being sent. It's an intermediate step in between composing and Sent. The only time something should be in there is right after you send a PM with large attachments (you may not even notice it) or if there was a problem sending it. It would remain in your outbox because it technically hasn't been sent.
Hope that makes sense.
yeah think of it as an outbox at work...things go there to be sent out....once they have been picked up it will go to the sent box.
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