Occasionally I am asked to "re-deliver" an inbound e-mail message by logging on to our edge Barracuda spam filter and re-sending it from there. I just did this the other day for a mailbox homed on our Exchange 2010 SP1 UR2 server, and discovered the joys of duplicate detection when multiple attempts to re-deliver a message did not result in the message showing up in the user's inbox. The following article explains how to tune duplicate message detection in Exchange 2007. http://technet.microsoft.com/en-us/library/dd577073(EXCHG.80).aspx. Despite my best efforts, I can't find similar information for 2010. Is duplicate message detection documented anywhere for 2010? Does the same information hold for 2010 that did for 2007? Thanks, RS

Per my research, exchange 2010 uses the same method as exchange 2007 for Duplicate Message DetectionPlease remember to click Mark as Answer on the post that helps you, and to click Unmark as Answer if a marked post does not actually answer your question. This can be beneficial to other community members reading the thread.