Hi There, Any suggestions would be appreciated. The problem is this: On Feb 13 the Windows updates below were automatically installed and the Windows 2003 Standard (DC) server running Exchange 2003 Standardautomatically rebooted. Following the reboot the Exchange stores failed to mount automatically. Attempts to manually mount them were successful so this isn't urgent. Since the server also runs Blackberry Enterprise Server the BES services were set to manual and the server was rebooted again (I wanted to get BES out of the equation). The same problem occured ... stores failed to mount but could be mounted manually. The following event show up in the log: Event Type: Error Event Source: MSExchangeSA Event Category: MAPI Session Event ID: 9175 Date: 2/13/2008 Time: 3:18:30 AM User: N/A Computer: SERVER Description: The MAPI call 'OpenMsgStore' failed with the following error: The Microsoft Exchange Server computer is not available. Either there are network problems or the Microsoft Exchange Server computer is down for maintenance. The MAPI provider failed. Microsoft Exchange Server Information Store ID no: 8004011d-0526-00000000 Here is the list of the patches that were installed before the problem occured: MS08-007: Vulnerability in WebDAV Mini-Redirector could allow remote code execution MS08-006: Vulnerability in Internet Information Services could allow remote code execution MS08-005: Vulnerability in Internet Information Services could allow elevation of privileges MS08-003: Description of the security update for Active Directory in Windows 2000 Server and in Windows Server 2003: February 12, 2008 MS08-008: Description of the security update for Windows 2000, for Windows XP, for Windows Server 2003, and for Windows Vista: February 12, 2008 Thanks in advance for any advice or assistance with further troubleshooting this issue. Steve

It should be related to server perfomance. When you startup the server, your server busy for startup some serivces. if your server doesn't have this problem before, it may be busy on update some services/compont. This problem may not reoccur on et reboot.

Hi Chaub, thanks for the suggestion but the problem, what you are saying makes sense but theproblemoccured on 2 reboots that were peformed several days after the initial incident. Steve

Hi, This problem should be relate to performance issues. If you can split the DC & Exhange in 2 machines should be better. if not, you can try to Disk defragment & Exchange DB defragment.

Thanks to everyone that responded. The solution turned out to be the most obvious thing. So obvious I didn't even think to check it and people probably weren't suggesting it in case they insulted my intelligence. Somehow, following the install of the patches the check box "Do not mount this storeat start-up" got checked. I'm the only one that manages Exchange and I know I didn't do this so somehow a Windows Update must have done it (Ishudder to think about other possibilities). Anyway if anyone else has had this issue it would be helpful to confirm my assumption. Steve

Hello Steve, I can confirm, that the same thing happened to me. L-E-OT