This article was previously published under Q325641
If a client that is located behind a domain controller that has only one network adapter uses Active Directory tools such as Active Directory Users and Computers and tries to connect to some multihomed domain controllers, the client may try to connect to both IP addresses for that domain controller. If the connection to one of the IP address does not work, the overall connection attempt does not succeed and the client receives the following error message:
Unable to connect to the domain controller because the server is not operational
The following sample scenario demonstrates this problem:
A client in Des Moines tries to connect to a multihomed domain controller in Honolulu that has 130.x.x.x and 140.x.x.x IP address. Although the Des Moines client is on the 140.x.x.x segment, the client tries to synchronize with both IP addresses. The client connects correctly to the 140.x.x.x address but receives a "Host unreachable" response from the 130.x.x.x attempts because this is not a routable IP address for internal use. The client continually retries to connect to the 130.x.x.x IP address. Eventually, the connection attempt does not succeed, and the client disconnects from the 140.x.x.x address also. This causes the error message to occur.
The Lightweight Directory Access Protocol (LDAP) client retrieves all of the IP addresses for the server from DNS. If there is more than one IP address, the client queries all of them. If one of the connections times out early during the connection, the whole connection attempt does not succeed. There is no additional attempt to retry the other IP address connections.
Service Pack Information
To resolve this problem, obtain the latest service pack for Microsoft Windows 2000. For additional information, click the following article number to view the article in the Microsoft Knowledge Base:
260910 How to Obtain the Latest Windows 2000 Service Pack
A supported hotfix is available from Microsoft. However, this hotfix is intended to correct only the problem that is described in this article. Apply this hotfix only to systems that are experiencing this specific problem.
If the hotfix is available for download, there is a "Hotfix download available" section at the top of this Knowledge Base article. If this section does not appear, submit a request to Microsoft Customer Service and Support to obtain the hotfix.
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