This is Outlook 2007 connected to Exchange Server 2003 in cached exchange mode.
I got a call today from a customer. He went into Outlook and was alarmed to see that it was downloading 4500 new mail messages. It turned out however that for every message in his mailbox, Outlook was downloading 2 more duplicates. So for every original message, there are now 3 messages.
I deleted the profile and recreated it. And exactly the same happened. What is happening here?
edit: It's not exactly 2 duplicates. Some messages only have a single duplicate and some are not duplicated at all. I