What type of mail server are you using?
Outlook has never saved sent items to the Inbox before. They either go to
the Sent Items folder or to the folder where the message you are replying
to is if it isn't in the Inbox.
Actually, I understand the symptom, as I have a user here who just
reported the same issue.
When the user replies to, or forwards a message that was in the Inbox,
the original message that was in the Inbox disappears and only the
record of the sent item remains in the Sent Items folder. Normally,
replying to a message will leave that message in the Inbox.
In our environment, we moved to Exchange 2007 with Outlook 2003/2007
clients after spending a number of years on a generic mail server.
Under the generic mail server, mail was kept in Outlook in PST files.
Now, under Exchange 2007, the users have OST files. The mail from the
PST files were imported into the OST file, and the PST files were
removed from the users' accounts.
On a hunch, I decided to open the old PST file. As it turns out,
Outlook had the "missing" messages (the ones that "disappeared" from
the Inbox in the OST file) in the PST file.
I'd like to know why, and how to fix it.
~HikingStick
~Andrew James Riemer