XCON: Mail Is Not Delivered When It Is Sent from a Mixed Routing Group (329355)

SYMPTOMS

In a mixed-mode Exchange organization, when you send mail from Exchange 2000 servers in mixed routing groups to Exchange 2000 servers in pure Exchange 2000 routing groups, you may find that mail is not delivered.

Note "Mixed" routing groups contain both Exchange Server 5.5 computers and Exchange 2000 computers. "Pure" Exchange 2000 routing groups contain only Exchange 2000 servers.

CAUSE

This issue may occur if all the following conditions are true:

The sender's mailbox is on an Exchange 2000 server in a mixed routing group.
The recipient's mailbox is in a pure Exchange 2000 routing group.
The source and destination routing groups are connected through a pure Exchange Server 5.5 routing group (hub routing group).
The source and hub routing groups are connected by an X.400 Connector or a site routing group connector.

RESOLUTION

To resolve this issue, verify that routing group names match the associated administrative groups. To do so, use one of the following methods:

Use the WinRoute tool. WinRoute is recommended for large organization with many administrative groups.

For additional information about how to obtain and use WinRoute, click the following article number to view the article in the Microsoft Knowledge Base:
281382 XCON: How to Use the WinRoute Tool
Use Exchange System Manager. To do so, follow these step:
1. Start Exchange System Manager, and then connect to an Exchange server.
2. Expand the Organization container to see the routing groups in the upper window pane. The routing group objects use following syntax:
  RG: ROUTING_GROUP_NAME (ADMIN_GROUP_NAME) (VERSION_INFO)
3. If the ROUTING_GROUP_NAME and ADMIN_GROUP_NAME do not match, rename the routing group. To do so,
  1. Right-click the routing group, and then click Rename.
  2. Type the name of the administrative group.
    
    Note In an environment with multiple global catalog servers, the updated routing might not work properly until the change has replicated between the global catalogs.

WORKAROUND

To work around this issue, use one of the following methods:

Create a connector directly between the source and target server, and add the target routing group to the Connected Routing Group tab of the connector.
Add the target routing group to the Connected Routing Groups tab of the X.400 Connector or site connector that connects the source and the hub routing group.

MORE INFORMATION

When you use Exchange System Manager to create a new administrative group, the group does not contain any sub-containers. You can create system policy containers and public folder containers in the administrative group, but you cannot create a routing group container. If you install an Exchange 2000 server in this group, you are not prompted for a name for the routing group. Setup automatically creates a routing group named "First Routing Group," and makes the new server a member of this routing group.

If you create an X.400 Connector on an Exchange Server 5.5 computer, you can only specify the target site and target domain because Exchange Server 5.5 computers do not support routing groups. Therefore, the routing group must have the same name as its administrative group.

The following restrictions apply to Exchange 2000 when Exchange 2000 is running in mixed-mode:

Exchange Server 5.0 and 5.5 sites are mapped directly to administrative groups.
Administrative groups are mapped directly to Exchange Server 5.0 and 5.5 sites.

The following restrictions apply to Exchange 2000 in a mixed-mode organization, where mail is routed using an Exchange Server 5.5 administrative group, an X.400 Connector, or a site connector:

There must be a one-to-one mapping between administrative groups and sites.
The name of the administrative group must match its associated routing group.

For additional information about mixed mode and native mode in Exchange 2000, click the following article number to view the article in the Microsoft Knowledge Base:

270143 XADM: Mixed Mode vs. Native Mode