Hello all,I have an Exchange 2007 RTM server that has been in use for about 5 months now. It has the Hub, Mailbox, and CAS roles. Server is running Windows Server 2003 R2 64-bit andupdates, patches are all current. The clients are all Outlook 2007, Outlook 2003, OWA, and ActiveSync clients. There are two domain controllers in the domain and there is only one domain in this forest. One of the domain controllers is the Global Catalog server and as far as I can figure out, the DNS entries are correct. Recently, after a reboot of the server the error messages shown below started appearing in the event log. The DC1 serverwas setup as the global catalog server several months ago and has been rebooted several times after that. Exchange appears to be operating normally, but I am trying to find out why this problem occurred. I'd greatly appreciate any advice and suggestions. Thanks!I should mention that memory usage in the Exchange server has gone up significantly in the past 3~4 weeks. The server has 8 GB of RAM and memory use was in the 4 ~ 6 GB range and now it is in the 9 ~ 11 GB range with store.exe taking up roughly 7 GB. The storage group size isroughly 65 GB. I posted this in this forum a couple of weeks ago, but didn't find a solution. Thank you. Event Type: Error Event Source: MSExchangeSA Event Category: RFR Interface Event ID: 9074 Date: 1/5/2009 Time: 10:56:34 AM User: N/A Computer:XCHG Description: The Directory Service Referral interface failed to service a client request. RFRI is returning the error code:[0x3f0]. For more information, see Help and Support Center at http://go.microsoft.com/fwlink/events.asp. Event Type: Error Event Source: MSExchangeSA Event Category: RFR Interface Event ID: 9143 Date: 1/5/2009 Time: 10:56:27 AM User: N/A Computer:XCHG Description: Referral Interface cannot contact any Global Catalog that supports the NSPI Service. Clients making RFR requests will fail to connect until a Global Catalog becomes available again. After a Domain Controller is promoted to a Global Catalog, it must be rebooted to support MAPI Clients. For more information, see Help and Support Center at http://go.microsoft.com/fwlink/events.asp. Event Type: Error Event Source: MSExchangeSA Event Category: NSPI Proxy Event ID: 9176 Date: 1/5/2009 Time: 10:56:27 AM User: N/A Computer:XCHG Description: NSPI Proxy can contact Global Catalog DC1.x.y.com but it does not support the NSPI service. After a Domain Controller is promoted to a Global Catalog, the Global Catalog must be rebooted to support MAPI Clients. RebootDC1.x.y.com as soon as possible. For more information, see Help and Support Center at http://go.microsoft.com/fwlink/events.asp.

Hi,Based on my research, these event logs indicate that your Exchange server may encounter a short time communication problem with your GC. Based on my experience, I think the some possible causes for this kind of issues are:1: The network between them may occur a short-time malfunction.2: The GC server may occur a short-time response delay.3: The CPU resource may be completely occupied by other application on your GC such as antivirus software.Hence, in order to check the related settings and make sure your Exchange server is working correctly now, we need to use these steps to check the status of your Exchange server:1: In your Exchange server, try to check if the communication between your Exchange server and GC successfully by using ping tool.2: In your Exchange server, try to check the DNS setting and investigate if you have configured any External DNS which may cause your Exchange server cannot recognize your GC normally.3: Open the Exchange System Manager, right click your Exchange server and choose properties->Directory Access and check if the Global Catalog was be discovered automatically.Additionally, please run EXBPA tool to diagnose the Exchange server. http://technet.microsoft.com/en-us/exchange/bb288481.aspx Thanks Allen

Allen,Thank you for your reply. With respect to your questions:1. Ping time between exchange server and GC is < 1ms for ping -n 1000 and no losses.2. Exchange server is configured to use the network card DNS settings and all DNS servers configured are internal DNS servers.3. In the Exchange Management Console, Server configuration -> Exchange server -> Properties -> General tab shows the correct global catalog server name. I have run the Exchange best practices analyzer several times and the only warning I get is regarding putting both database and log files in the same volume.I look forward to hearing from you. Thanks!

Allen, I forgot to mention, this server is connected to a Cisco 3560G switch and the spanning tree mode for this port has been set to Portfast. The switch port comes online in < 1s. Thanks!

Hi,It seems that no obvious issue exists on the Exchange server from the evidence.Whether the error message still continuous appearing in the event log? If not, maybe that is just the temporary communication malfunction. We can monitor this issue.ThanksAllen

Hi Allen,No, the errors only appeared on the event log immediately after rebooting the server (And they appear consistently every time the server was rebooted). There were no occurrences after that. Is there anything I can do to keep track of this situation apart from checking the event log? Thanks!

Hi,we can run nltestcommand to check whether the DC isdetected from Exchange server. Open a command promt, input the following command:nltest /dsgetdc:domain.com /gc /forceThanksAllen

Hi Allen,I ran the command (sorry for the delay, I had to install the Support Tools pack) and the output correctly identifies the GC server. This is getting quite puzzling. Thanks!

Hi,Was there only one GC in the environment? It it is, that is normal since Exchange was unable to contact GC due to GC was restarting.Please understand that NSPI Proxy and Referral Service are the components of DSProxy which gets its list of working GC servers from DSAccess that provides Outlook (MAPI) clients with an address book service.Thus, if the GC was restarting that will cause theDSAccess could not connect GC, then the DSProxy will fail and come up error message.ThanksAllen

Hi Allen,The GC is a separate server. The error messages are cropping up in my Exchange Hub + Mailbox + CAS server. I have two domain controllers, one of which is the GC. At the time the Exchange server was being rebooted, the GC server was up and running OK.Thanks!

Hi Allen.Just an update; I updated andrebooted my Windows 2003 servers over the weekend. TheDC + GC server was rebooted first and the Exchange server was rebooted about30 minutes later. I got the same sequence of error messages that I posted in the first message of this thread. Thanks!

Hi,Please try DCDiag command to do further test. The command is DCDiag /s DC's name /Test:ConnectivityWhat's the result?After that, please run DCDiag /s DC's name /eAnd let me know the outcome that you test.ThanksAllen

Hi Allen,No anomalies detected. Here's the result from the last command (/e): Domain Controller Diagnosis Performing initial setup: Done gathering initial info. Doing initial required tests Testing server: Default-First-Site-Name\DC1 Starting test: Connectivity ......................... DC1 passed test Connectivity Testing server: Default-First-Site-Name\DC2 Starting test: Connectivity ......................... DC2 passed test Connectivity Doing primary tests Testing server: Default-First-Site-Name\DC1 Starting test: Replications ......................... DC1 passed test Replications Starting test: NCSecDesc ......................... DC1 passed test NCSecDesc Starting test: NetLogons ......................... DC1 passed test NetLogons Starting test: Advertising ......................... DC1 passed test Advertising Starting test: KnowsOfRoleHolders ......................... DC1 passed test KnowsOfRoleHolders Starting test: RidManager ......................... DC1 passed test RidManager Starting test: MachineAccount ......................... DC1 passed test MachineAccount Starting test: Services ......................... DC1 passed test Services Starting test: ObjectsReplicated ......................... DC1 passed test ObjectsReplicated Starting test: frssysvol ......................... DC1 passed test frssysvol Starting test: frsevent ......................... DC1 passed test frsevent Starting test: kccevent ......................... DC1 passed test kccevent Starting test: systemlog ......................... DC1 passed test systemlog Starting test: VerifyReferences ......................... DC1 passed test VerifyReferences Testing server: Default-First-Site-Name\DC2 Starting test: Replications ......................... DC2 passed test Replications Starting test: NCSecDesc ......................... DC2 passed test NCSecDesc Starting test: NetLogons ......................... DC2 passed test NetLogons Starting test: Advertising ......................... DC2 passed test Advertising Starting test: KnowsOfRoleHolders ......................... DC2 passed test KnowsOfRoleHolders Starting test: RidManager ......................... DC2 passed test RidManager Starting test: MachineAccount ......................... DC2 passed test MachineAccount Starting test: Services ......................... DC2 passed test Services Starting test: ObjectsReplicated ......................... DC2 passed test ObjectsReplicated Starting test: frssysvol ......................... DC2 passed test frssysvol Starting test: frsevent ......................... DC2 passed test frsevent Starting test: kccevent ......................... DC2 passed test kccevent Starting test: systemlog ......................... DC2 passed test systemlog Starting test: VerifyReferences ......................... DC2 passed test VerifyReferences Running partition tests on : ForestDnsZones Starting test: CrossRefValidation ......................... ForestDnsZones passed test CrossRefValidation Starting test: CheckSDRefDom ......................... ForestDnsZones passed test CheckSDRefDom Running partition tests on : DomainDnsZones Starting test: CrossRefValidation ......................... DomainDnsZones passed test CrossRefValidation Starting test: CheckSDRefDom ......................... DomainDnsZones passed test CheckSDRefDom Running partition tests on : Schema Starting test: CrossRefValidation ......................... Schema passed test CrossRefValidation Starting test: CheckSDRefDom ......................... Schema passed test CheckSDRefDom Running partition tests on : Configuration Starting test: CrossRefValidation ......................... Configuration passed test CrossRefValidation Starting test: CheckSDRefDom ......................... Configuration passed test CheckSDRefDom Running partition tests on : ad1 Starting test: CrossRefValidation ......................... ad1 passed test CrossRefValidation Starting test: CheckSDRefDom ......................... ad1 passed test CheckSDRefDom Running enterprise tests on : ad1.x.com Starting test: Intersite ......................... ad1.x.com passed test Intersite Starting test: FsmoCheck ......................... ad1.x.com passed test FsmoCheck Thanks!