For the last 2 weeks we have been having this issue with our Exchange 2007 SP1 RU9 environment. We have a clustered mailbox server (physical) and a clustered CAS/transport server (virtual) We are running Forefront for Exchange SP2 FCS with latest updates and proper exclusions and EHS spam filtering Basically out of no where we get disconnected from exchange then reconnected or all the datastores dismount. We have rebooted, failed over, run all windows and exchange updates. data store defrags. data store integrity checks. here are the errors we are getting The Microsoft Exchange Information Store service terminated unexpectedly. It has done this 5 time(s). - <Event xmlns="http://schemas.microsoft.com/win/2004/08/events/event"> + <System> <Provider Name="Service Control Manager" Guid="{555908D1-A6D7-4695-8E1E-26931D2012F4}" EventSourceName="Service Control Manager" /> <EventID Qualifiers="49152">7034</EventID> <Version>0</Version> <Level>2</Level> <Task>0</Task> <Opcode>0</Opcode> <Keywords>0x80000000000000</Keywords> <TimeCreated SystemTime="2009-11-10T05:04:50.000Z" /> <EventRecordID>73790</EventRecordID> <Correlation /> <Execution ProcessID="0" ThreadID="0" /> <Channel>System</Channel> <Computer>CAACALEXFN2.domain.COM</Computer> <Security /> </System> - <EventData> <Data Name="param1">Microsoft Exchange Information Store</Data> <Data Name="param2">5</Data> </EventData> </Event> Cluster resource 'Exchange Information Store Instance (CAACALMBX01)' in clustered service or application 'CAACALMBX01' failed. - <Event xmlns="http://schemas.microsoft.com/win/2004/08/events/event"> - <System> <Provider Name="Microsoft-Windows-FailoverClustering" Guid="{baf908ea-3421-4ca9-9b84-6689b8c6f85f}" /> <EventID>1069</EventID> <Version>0</Version> <Level>2</Level> <Task>3</Task> <Opcode>0</Opcode> <Keywords>0x8000000000000000</Keywords> <TimeCreated SystemTime="2009-11-10T05:04:50.840Z" /> <EventRecordID>73791</EventRecordID> <Correlation /> <Execution ProcessID="4616" ThreadID="8104" /> <Channel>System</Channel> <Computer>CAACALEXFN2.domain.COM</Computer> <Security UserID="S-1-5-18" /> </System> - <EventData> <Data Name="ResourceName">Exchange Information Store Instance (CAACALMBX01)</Data> <Data Name="ResourceGroup">CAACALMBX01</Data> </EventData> </Event> I think our next idea is to install exchange sp2 but any ideas would be helpful. ThanksSystems Administrator

Yes i would suggest you to go for exchange 2007 sp2. also make sure your AV is not scanning the IS excessively. and you have set the Paging File etc as for the recommendation. I would also scan the Server with EXBPA to make sure everythig looks goodVinod |CCNA|MCSE 2003 +Messaging|MCTS|ITIL V3|

So we noticed we were getting this error almost every time just before the store.exe file crashed An inconsistency was detected in robinsonda@domain.com: /Calendar/Safety Improvement Status Update.EML. The calendar is being repaired. If a problem persists, please recreate the calendar or the containing mailbox. we moved the users mailbox to its own data store and brought it offline.... nothing has crashed in the last 9 hours.... is it posible this was crashing everything else?Systems Administrator

It is hard to say.But if we have corrupt item in the store,it could cause the issue.Top support issues for the Exchange information storehttp://support.microsoft.com/default.aspx/kb/893083Regards,Xiu