I've been having some odd problems on my Exchange 2003 SP2 server that started last week. I'm not sure what is causing this but here is a rundown of the problems: I got this error on two of my five stores: Event ID 623 Information Store (2936) Back Office 2: The version store for this instance (0) has reached its maximum size of 108Mb. It is likely that a long-running transaction is preventing cleanup of the version store and causing it to build up in size. Updates will be rejected until the long-running transaction has been completely committed or rolled back. Possible long-running transaction: SessionId: 0xBD330A20 Session-context: 0x00000000 Session-context ThreadId: 0x0000156C Cleanup: 1 This error follows: Event ID 9791 Cleanup of the DeliveredTo table for database 'DB PATH' was pre-empted because the database engine's version store was growing too large. 0 entries were purged. This would be followed by this error for a variety of accounts: Event ID 9646 Mapi session "/O=PATH/OU=PATH/cn=Recipients/cn=USER" exceeded the maximum of 250 objects of type "objtMessage". and Event ID 1022 Logon Failure on database "DB PATH" - Windows 2000 account CUNJ\gfi; mailbox /O=PATH/OU=PATH/cn=Recipients/cn=USERNAME. Error: -1069 There was obviously a problem with the mailbox stores so I created a new one and migrated the users to it. I'm still getting errors 9646 (though less of them) and also a new error this morning: Event ID 8263 The recurring appointment expansion in mailbox USERNAME has taken too long. Some recurring appointment instances may not be visible at this time. To ensure that the calendar view is correct, please refresh the calendar view in Microsoft Outlook Web Access. I'm at a loss. Can anyone help me determine what the root cause of these errors are and how I might be able to fix it? Users do seem to be able to operate Outlook though I have many reports of very slow performance. I would very much appreciate any help, thank you!

Event ID 623 Information Store (2936) Back Office 2: The version store for this instance (0) has reached its maximum size of 108Mb. It is likely that a long-running transaction is preventing cleanup of the version store and causing it to build up in size. Updates will be rejected until the long-running transaction has been completely committed or rolled back. Possible long-running transaction: SessionId: 0xBD330A20 Session-context: 0x00000000 Session-context ThreadId: 0x0000156C Cleanup: 1 This error follows: This Error denotes - The Database is not in a good state. Move your mailbox to a different store or Dismount your store locate your command prompt to Bin Folder . Exchange installation Location and run the below command isinteg -s "Servername" -fix -test alltests which fixes error in the database if above doesnt' fix Mount a blank store and Use recovery storage group to recover data "Outlook profile has to be recreated , As opening Outlook will prompt for Temp or Orginal mailbox" Satheshwaran Manoharan | Exchange 2003/2007/2010 | Blog:http://www.careexchange.in | Please mark it as an answer if it really helps you

I've already tried moving mailboxes to newly created stores last night but still get the error. I will try running the isinteg fix tonight and let you know if that works, thank you!

It seems to be the same issue as http://social.technet.microsoft.com/Forums/en-US/exchangesvrgeneral/thread/430d5631-b13a-41c5-b469-b44ca54db034/#46407a36-3a5e-4295-bb84-f43550a863cc Xiu Zhang TechNet Community Support