Microsoft small business knowledge base

Article ID: 245172 - Last Review: February 27, 2007 - Revision: 2.2

This article was previously published under Q245172


When you attempt to establish a trust relationship from a trusting domain by connecting to a primary domain controller (PDC) running Microsoft Windows NT Server 4.0 in a trusted domain, you may receive the following error message:
Could not find domain controller for this domain.


This behavior can occur if the 1b (domain master browser) and 1c (domain controller) NetBIOS names for the PDC in the trusted domain are not registered in the Windows Internet Naming Service (WINS). This can occur when the WINS servers in the two domains do not replicate to each other.


To resolve this issue, modify the Lmhosts file that contains the 1b and 1c entries for the PDC of the trusted domain:
  1. In a text editor (such as Notepad), open the Lmhosts file located in the %SystemRoot%\System32\drivers\etc folder.
  2. Add the following lines to the Lmhosts file, using the name of the trusted domain, the Internet Protocol (IP) address, and the NetBIOS name of the PDC in the trusted domain, as indicated in the following example:   PDCName   #PRE #DOM:DomainName   "DOMAINNAME     \0x1b"   #PRE
    • Replace in the example with the IP address of the PDC in the trusted domain.

    • Replace the PDCName with the NetBIOS name of the trusted domain PDC. When you specify the NetBIOS suffix (the sixteenth character), the spacing between the quotation marks is critical. There must be a total of 20 characters within the quotation marks (the domain name plus the appropriate number of spaces to pad up to 15 characters plus the backslash (\) plus the NetBIOS hex representation of the service type).

    • Replace DomainName with the Windows NT 4.0 domain name of the trusted domain.

  3. Save the changes to the Lmhosts file.
  4. Specify the use of the Lmhosts file:
    1. In Control Panel, double-click Network.
    2. Click the Protocols tab.
    3. In the Network Protocols box, click TCP/IP Protocol, and then click Properties.
    4. In the WINS Address tab, click the Enable LMHOSTS Lookup check box, and then click OK.
  5. Click Yes when you are prompted to restart your computer.


This behavior can also occur if you manually added the RestrictAnonymous registry value to the registry on the PDC of the trusted domain. This value prevents null session connections. In addition, this registry value also prevents a trusting domain from connecting to the PDC in the trusted domain to establish a trust relationship.

For information about establishing a trust relationship between domains, please see the following article in the Microsoft Knowledge Base:
178640  ( ) Could Not Find Domain Controller When Establishing a Trust
For more information about using an Lmhosts file, please see the following articles in the Microsoft Knowledge Base:
180094  ( ) How to Write an LMHOSTS File for Domain Validation
163409  ( ) NetBIOS Suffixes (16th Character of the NetBIOS Name)

  • Microsoft Windows 2000 Server
  • Microsoft Windows 2000 Advanced Server
  • Microsoft Windows 2000 Professional Edition
  • Microsoft Windows 2000 Datacenter Server
  • Microsoft Windows NT Server 4.0 Standard Edition
kbprb KB245172
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