You receive an HTTP 503 error message or an HTTP 500 error message when you access your mailbox by using Outlook Web Access through a front-end Exchange Server 2003 computer

When you access your mailbox by using Microsoft Outlook Web Access (OWA) through a front-end Microsoft Exchange Server 2003 computer, you receive one of the following error messages:

This problem occurs if the NetworkAddress property of any one of the Exchange server objects in the Active Directory directory service is not set to include the fully qualified domain name (FQDN) of the server. Typically, the NetworkAddress property of an Exchange server object is not set if any one of the following conditions is true:

• When you installed a new back-end Exchange server, you used the option that does not start the System Attendant service when Setup is finished.
• When you installed a new back-end Exchange server, Setup was not successfully completed.
• You successfully installed a new back-end Exchange server. However, replication problems prevent the replication of the NetworkAddress property to all domain controllers.

Note The back-end servers can be running any version of Exchange.

To resolve this problem, use one of the following methods, depending on your situation.

Method 1: Restart the System Attendant service

1. Restart the System Attendant service on the newly installed back-end Exchange server. The NetworkAddress property of a newly installed Exchange server object is set when the System Attendant service starts for the first time.
2. Use OWA to verify access to your mailbox.

Method 2: Correct the initial Setup problem

1. Verify your event logs and the Exchange log file to identify and to correct the initial Setup problem.
2. Restart the System Attendant service.
3. Use OWA to verify access to your mailbox.

Method 3: Manually set the NetworkAddress property

If the problem is not resolved by method 1 or by method 2, you must manually set the NetworkAddress property to temporarily resolve the problem. Then, verify that the NetworkAddress property is correctly replicated to all domain controllers. To do this, follow these steps:

1. On a computer that has the Windows Support Tools installed, click Start, click Run, type adsiedit.msc, and then click OK.
2. On the Action menu, click Connect to.
3. In the Computer area, click Select or type a domain or server.
4. Type the name of the domain controller to which you want to connect, and then click OK.
5. Expand Configuration, and then expand CN=Configuration, DC=Domain_Name, DC=Root_Domain.
6. Expand Services, expand Microsoft Exchange, and then expand Organization_Name.
7. Expand Administrative groups, expand Administrative_Group_Name, and then expand Servers.
8. Right-click the Exchange server object with which you want to work, and then click Properties. If you are not sure which Exchange server causes the problem, verify the NetworkAddress property of each Exchange server object.
9. In the Attribute column, double-click NetworkAddress.
10. In the Value to add box, type ncacn_ip_tcp:Server_Name.Domain_Name.Root_ Domain, where the text to the right of the colon (:) corresponds to the FQDN of the server. Then, click Add.
    
    Note You can use the existing value from another server object as a template. Look for the entry that has the "ncanc_ip_tcp" text string.
11. Click OK two times.
12. Quit the ADSI Edit snap-in.
13. Restart the World Wide Web Publishing service on each front-end Exchange 2003 computer that serves OWA users.
14. Verify that the NetworkAddress property is correctly replicated to all domain controllers.
15. Use OWA to verify access to your mailbox.