I've seen a lot of similar posts to this, but none describe this issue exactly. I have a hybrid environment of Exchange 2003 (over 1000 mailboxes) and Exchange 2010 (about 40 migrated mailboxes). This last Friday, I received a report that one of the 2010 mailboxes was sending out an old Out of Office Message that the user had since replaced with a new one (OOO for mid July). By the end of the day I had four similar reports on different 2010 mailboxes (the others had removed their OOM setting, but their mailbox was still sending out the old message) I was able to remove the OOM by opening the account in Outlook 2003, which reported the OOM ON, removing the setting and removing the text (but not using OWA, I'd had the users try this first). NOTE: The clients range from Outlook 2007 to Outlook 2011 (for MAC) to OWA. After further testing, I discovered at least one of the group could no longer get OOM's to deliver, even when they set the "away" setting. Today, I've discovered two others, not in the original group, are unable to get their OOM's to deliver. This problem does not seem to be effecting the 2003 mailboxes. ~bc

Have you tried seeing if you get more information from the shell than Outlook? Try running "get-mailboxautoreplyconfiguration" against the user(s) and see if you still see any old settings there.

Keep in mind that oofs are sent once every 24hrs per same email address. If it's not sending oofs to new emails senders when testing, open mfcmapi and see if the pr off state is set to true. Make sure Outlook is closed and then start MFCMapi.exe In the main window choose; Session-> Logon and Display Store Table Select the Outlook mail profile to logon to when prompted. If you do not recognize this dialog, simply press OK to load you default Outlook mail profile. Youll now see a list of your configured message stores in your mail profile. Select your mailbox by looking at the Display Name column. In the pane below, some properties will get loaded. Look at the Property Name(s) column and select the entry called; PR_OOF_STATE When you look at the Value column for this property, youll see it is now set to True. James Chong MCITP | EA | EMA; MCSE | M+, S+ Security+, Project+, ITIL msexchangetips.blogspot.com

Yes, I know this. I ensured that this wasn't a factor in my testing.~bc

I've just used MFCMapi to check four of the effected 40 or so mailboxes. None had multiple OOF rules that I could find. It's also interesting that ALL of my 40 or so 2010 mailboxes had OOMessaging fail the same day. My several thousand 2003 users are uneffected. I am seeing error messages in at least some of the mailboxes when I use MFCMapi, however. Trying to figure out how to interpret them. ~bc

Have you tried testing moving one of the mailboxes to another DB?James Chong MCITP | EA | EMA; MCSE | M+, S+ Security+, Project+, ITIL msexchangetips.blogspot.com

I just now tried that with one of the mailboxes, no change. Please note, the affected mailboxes are spread across several databases.~bc