Out Of Office Assistant doesn’t work properly or sends when disabled

We use Microsoft Exchange 2010 and Outlook 2010 at our office and recently ran into an interesting issue.  One of our remote office workers discovered that her Out Of Office Assistant (OoO) did not work during the specified dates.  Then, to our surprise, it started working a week later—sending out the message that it should have been sent the week before.

After confirming this was actually the case, we attempted to fix the problem by toggling the OoO on and off via the client, OWA and Power Shell, creating new Outlook client profiles, and restarting the various services.  None of these options worked.

Further research led us to the conclusion that the Out of Office Rules had been corrupted.

We searched numerous support blogs and  found an executable tool called MFCmapi which provides a GUI component that allows editing of individual Exchange mailbox properties. This tool allowed us to remove the corrupted OoO Rules from the affected user’s mailbox.  The tool can be downloaded from http://mfcmapi.codeplex.com/ .  

 The steps to remove the corrupted OoO Rules are:

•      Open the affected mailbox using the Microsoft Outlook client.
•      Launch the MFCmapi.exe application.
•      Click the OK button at the startup screen.
•      From the menu, select QuickStart then Open Folder \ InBox.
•      A login box will appear.  Select the affected user mailbox profile then press OK.
•      After a short time, an INBOX window will open in addition to the 1st.  It will list all of the InBox items.  
o      CLOSE THE INBOX WINDOW – WE DO NOT NEED IT
•      Switch to the MFCmapi x86 window.
•      Locate the affected user’s mailbox under DISPLAY NAME and double-click it.  
•      A separate window will open.
•      Expand the ROOT CONTAINER item.
•      Expand the TOP OF INFORMATION STORE item.
•      Locate the INBOX and right-mouse click on it.
•      Select OPEN ASSOCIATED CONTENTS TABLE from the pull down menu.
o      This is where the InBox HIDDEN messages are stored.
•      Another window named INBOX will open.  This is the one you want.
•      Scroll to the right in the visible window until you find MESSAGE CLASS.
•      Expand the MESSAGE CLASS column until you can read the items listed.
•      Sort the MESSAGE CLASS column as you would any Excel or E-mail column by clicking the column header.
•      Look for the messages with the following MESSAGE CLASSes:
o      IPM.Note.Rules.OofTemplate.Microsoft
o      IPM.Note.Rules.ExternalOofTemplate.Microsoft
•      Highlight ALL of these items and press the DELETE key.
•      At the Delete Item box, confirm the delete by pressing OK.
•      This should clear up all of the errors and allow new OoO Rules to work correctly.