Hello, I have a E2K7 SP1 System and I get the following error in my application log: MAPI-Session'93d70a51-6399-45e6-a1b7-2419434129c5' exceeded the maximum of250 objects of type objtMessage.I would like troubleshoot this, but how doI match that strange code to an account? ThanksMichael

It is probably the User GUID. And the error is probably caused by a backup program. Microsoft MAPI program interface enforces certain implicit limits on the number of objects which can be opened by a process at one time; for folder objects this limit defaults to 500.You Can increase the limit bycreating the following registry entry.Inhkey_local_machine/SYSTEM/CurrentControlSet/Services/MSExchangeIS/ParametersSystem create anew new subkey calledMaxObjsPerMapiSession and inside that sub key create a newdword keycalledobjtFolder and change the decimal value to 2000.You will need to restart the Information Store service for the changed to take affect.MCSE: MCITP - Exchange Admin: MCTS - SQL 2005

Hey Mike,To find user based on GUID, follow below article...The description of the event ID 9646 message includes a GUID instead of a recipient namehttp://support.microsoft.com/kb/899663Check couple of below article for resolution, first check any third-party mapi application used by the user thenbehavior of user, how he is connecting to exchange server and if you couldn't find any clue then change the registry to increase the value of objMessage.An Exchange 2007 server stops responding to a MAPI client and logs event ID 9646 in the Application loghttp://support.microsoft.com/kb/925815http://technet.microsoft.com/en-us/library/bb676486.aspxAmit Tank | MVP - Exchange | MCITP:EMA MCSA:M | http://ExchangeShare.WordPress.com

Are you running Exchange 2007 on a Windows Server 2003? What service pack level do you have on the Windows server? I have seen similar issues with Windows 2003 SP2's scalable networking pack and it was resolved usinginformation from http://support.microsoft.com/default.aspx/kb/912222

You can match the GUID to a mailbox using the following cmdlet:get-mailbox -ResultSize unlimited | where {$_.ExchangeGuid -eq "a33236c3-14cc-4e8f-99da-cff05c84ecc4"}Obviously you need to change the GUID in thecmdlet to match the one in the log, and you do have to have the quote marks for it to work.Hope this helps!Lee Owens, MCSE, MCITP: Enterprise Messaging Administrator

Leeowens337 This is just what i needed. Thank you for posting!!!!!! Bill