Hi There, I'm having one Exchange 2003 SP2 (SBS) server with one mailbox store. Every a couple of days once , there is event ID 9175 logged Exchange server application log. Event Type: Error Event Source: MSExchangeSA Event Category: MAPI Session Event ID: 9175 User: N/A Computer: Exchange Description: The MAPI call 'OpenMsgStore' failed with the following error: The attempt to log on to the Microsoft Exchange Server computer has failed. The MAPI provider failed. Microsoft Exchange Server Information Store I've done some research and found that following link: http://support.microsoft.com/kb/274534/en-us I'm just wondering whether is it safe to delete the system mailbox object? Regards, Billy

Never try the adventure of deleting system attendant mail box. It can create a mess on the whole messaging system. For 9175 , if your stores are up and running, you can safely ignore it.Raj

Hi Raj, But the problem is the mailstore can only be mount manually instead of automatic. After a couple of days, I will need to manually mount it. Is there any other alternatives? Billy

So the information store service is stopping every few days by itself? Are you running file-level Anti Virus or any other 3rd party software on that server? Have you run ExBpa against the server? Anything else in the event logs when the info store stops on its own?

Billy, any other events that you are getting on the events log? If you can post the errors from Exbpa and DCDIAG. Also check the directory access tab in ESM .Raj

Hi Billy Please refer to this silmilar threads and enable diagnostic logging: http://social.technet.microsoft.com/forums/en-US/exchangesvradmin/thread/e2c34d32-9493-4e72-b8b7-1c16a65ccfbc http://social.technet.microsoft.com/Forums/en-US/exchangesvrgeneral/thread/b1b0b667-e766-4303-a24d-4eb242b2747e Thanks, Richard Your expertise never fails to impress :)

Have you any updates? Have you solve your prolbem?Your expertise never fails to impress!