Message filtering does not work in the Microsoft Exchange Internet Mail Service if the "Route to" option for a domain is set to "Relay" in Exchange Server 5.5

Consider the following scenario. You enable message filtering in the Microsoft Exchange Internet Mail Service in Microsoft Exchange Server 5.5. Then, you set the Route to option on the Routing tab for a domain to relay. When you set the Route to option to Override relay restrictions. Always "relay", relay message filtering does not always work.

To work around this problem, you must enable the RerouteViaStore registry value in the following registry subkey:If you set the RerouteViaStore value to 1, all SMTP messages are rerouted through the Microsoft Exchange Information Store service (Store.exe). To do this, follow these steps.

Warning Serious problems might occur if you modify the registry incorrectly by using Registry Editor or by using another method. These problems might require that you reinstall your operating system. Microsoft cannot guarantee that these problems can be solved. Modify the registry at your own risk.

1. Click Start, click Run, type Regedit, and then click OK.
2. Locate and then click the following registry subkey:
   HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\MSExchangeIMC\Parameters
3. On the Edit menu, point to New, and then click DWORD Value.
4. In the details pane, type RerouteViaStore for the new DWORD value.
5. In Edit DWORD Value dialog box, click Decimal under Base.
6. In the Value Data box, type 1, and then click OK.
7. Quit Registry Editor.

Microsoft has confirmed that this is a problem in the Microsoft products that are listed in the "Applies to" section.

For more information, click the following article numbers to view the articles in the Microsoft Knowledge Base: