Topic Last Modified: 2009-02-19

This topic provides information about how to troubleshoot an error message that occurs when users try to log on to Microsoft Office Outlook Web Access through the Client Access server role in Microsoft Exchange Server 2007. When users try to log on to Outlook Web Access, they receive the following error message:

Outlook Web Access did not initialize. An event has been logged so that the system administrator can resolve the issue. Please contact technical support for your organization.

Microsoft Exchange Active Directory Topology Service cannot be contacted via RPC interface, error 0x5.

This error occurs if the MSExchangeOWAAppPool application pool that is used to run Outlook Web Access is not configured to use the Local System account. Instead, MSExchangeOWAAppPool is configured to use the Local Service account or the Network Service account. The Local Service and Network Service accounts do not have the appropriate permissions to access the information store service. Therefore, logon to Outlook Web Access cannot be completed if the application pool is not using the LocalSystem account.

To resolve this issue, make sure that the /owa virtual directory is running in the Outlook Web Access application pool and that MSExchangeOWAAppPool is running under the Local System account.

To make sure that the /owa virtual directory is running in the Outlook Web Access application pool

  1. Start Internet Information Services (IIS) Manager.

  2. In the Connections pane, expand the Server_Name\Sites\Default Web Site node.

  3. Right-click owa, and then click Properties.

  4. On the Virtual Directory tab, make sure that the Application Pool is set to MSExchangeOWAAppPool.

To make sure that MSExchangeOWAAppPool is running under the Local System account

  1. Start Internet Information Services (IIS) Manager.

  2. In the Connections pane, expand the Server_Name\Application Pools node.

  3. Right-click MSExchangeOWAAppPool, and then click Properties.

  4. On the Identity tab, make sure that the security account is set to Predefined: LocalSystem.

Note:
You may have to verify that the other Exchange-related application pools are using the Local System account. For example, check the   MSExchangeAutodiscoverAppPool, MSExchangeServicesAppPool, MSExchangeSyncAppPool, and MSExchangeUMAppPool application pools.