We are a small office with 6 computers, running Exchange 2003 on office server. Each client computer has Mozilla Thunderbird installed with IMAP connection to Exchange Server.
Few days ago we discovered that there are emails missing in some mailboxes (receive period 09-2011 to 12-2011).
I have checked all folders, and deleted items, but the items just disappeared. Interesting fact is that some mailboxes did not experience this same problem. What should be the next step in order to locate and retrieve these items on Exchange?