We have been deploying an Exchange 2010 organisation over the last few days. There are three servers in the setup:Server 1 - Edge Transport Server RoleServer 2 - Hub Transport, Client Access, Mailbox Server RolesServers 1 and 2 are in the company's parent domain.Server 3 is in a seperate site, on a child domain. It currently has the Hub Transport and Client Access Server roles installed, and has subscribed successfully to the Edge Server, but we are unable to install the Mailbox Role.When running setup, the Information Store Service refuses to start with the following errors logged into the Application Log:Event 5000 - Unable to initialize the Microsoft Exchange Information Store Service. Failed to init VSERVER - Error 0x8004010fThat's a fairly generic event, so the previous event is therefore more relevant:Event 1201 - Error -2147221233 reading/decrypting the msExchResponsibleMTAServer attribute on the Server object in the Active Directory.Looking at ADSIEdit in: ConfigurationServicesMicrosoft Exchange<Organization Name>Administrative Groups<Administrative Group>ServersAnd getting the properties on the server object, we do indeed see that the msExchResponsibleMTAServer attribute is not set.Setting this however, in the appropriate format, replacing the servernames, domain names etc with the correct info:CN=Microsoft MTA,CN=SERVERNAME,CN=Servers,CN=Exchange Administrative Group (FYDIBOHF23SPDLT),CN=Administrative Groups,CN=ADMINGROUPNAME,CN=Microsoft Exchange,CN=Services,CN=Configuration,DC=DOMAIN,DC=DOMAINResults in the following error:Operation Failed, Error code: 0x20b5 - The name reference is invalid.At this point I am a little stuck! Any ideas very gratefully appreciated!Chris

Is there any other error info in the installation log? Is the error “0x20b5” returned when attempting to set the value of “msExchResponsibleMTAServer” attribute? Or, retry the installation? Does the “CN=Microsoft MTA” container exist under the server container? Please refer to KB 928811, although it’s for exchange 2007. You may refer the related value of another working exchange server in the parent domain James Luo TechNet Subscriber Support (http://technet.microsoft.com/en-us/subscriptions/ms788697.aspx) If you have any feedback on our support, please contact tngfb@microsoft.com