I was understood that Exchange 2010 has a "Duplicate Message Detection" feature however it does not appear to be working.
Often members of staff are manually dropping emails into public folders and is creating duplicate emails when other members of staff drop the same email into public folders. And I have to use Remove Duplicate Items (ODIR) to remove these items.
Surely with Exchange 2010 I should not need to do this? I am running SP 2 and Update Rollup 1.