‏ I rebuilt the main identity with no success. Seeking further advice and assistance. Thank you.
The Deleted Items folder is indeed empty. I am running version 14.2.3 which was installed today, July 12, 2012. This problem started today prior to the update installation.
Hi there,

I work in IT and in the last 2 weeks, I've seen a really nasty issue/bug with Outlook 2011 for Mac.  The only commonality was that both users had very large "Deleted Items" folders.  We have an Exchange 2010 environment and the client OS is Mac OS X 10.7.3.

Case #1, 2 weeks ago:
The user uses the "Deleted Items" folder to store email for reference, as they would with any other folder.  At some point, the deleted items began duplicating and caused the mailbox size to grow rapidly out of control.  Eventually, the user wasn't able to send or receive mail due to mailbox limits we have in place, and it's at that time the user alerted us to the issue.  At this time, the user had 98k items in the "Deleted Items" folder.  We ran a deduplication tool on the mailbox, but as soon as the Outlook 2011 client was opened again, the duplication happened again.  We tried a few other things, but the duplication would happen again as soon as Outlook 2011 was fired up.  We even tried uninstalling/reinstalling Outlook 2011, but that didn't help either.  We ended up nuking the entire mailbox and manually importing items from a .pst.

Case #2, happening now:
The user also uses the "Deleted Items" folder for storage.  He filed a helpdesk ticket stating that his Deleted Items folder is spiraling out of control and is duplicating items over and over again.  He re-created his Identity Database but the problem kept happening.  He's running the latest version,14.2.2, and installed the update prior to the issue occuring.

My question:  What can we do to fix this?  Is this a known-issue?