Microsoft KB Archive/273663

= Clients Cannot Find Domain Controller to Log On =

Article ID: 273663

Article Last Modified on 2/21/2007

-

APPLIES TO


 * Microsoft Windows 2000 Server
 * Microsoft Windows 2000 Advanced Server
 * Microsoft Windows 2000 Professional Edition

-



This article was previously published under Q273663



SYMPTOMS
Some client computers may be unable to locate a domain controller in a Windows 2000-based domain when the domain controllers are under a heavy load.



CAUSE
In part, a client computer finds a domain controller by performing an LDAP UDP &quot;ping&quot; on a list of candidate domain controllers. The quickest domain controller to respond is the one chosen for the client. If no domain controller responds, the client is not given a name of a domain controller to contact. These are time-sensitive UDP LDAP requests. If the domain controller is under heavy load, the LDAP head may not be able to respond to these requests fast enough. In that case, WinSock builds up a queue of requests for the LDAP head. To get to the more current LDAP pings, the server must get through the oldest, and probably expired, LDAP pings first. A heavily loaded domain controller may get bogged down answering expired LDAP pings, and never actually answer a current ping.



RESOLUTION
To resolve this problem, obtain the latest service pack for 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

The English version of this fix should have the following file attributes or later:   Date        Time    Version        Size    File name --  09/08/2000  2:52PM  5.0.2195.2158  32,016  Ntdsatq.dll



STATUS
Microsoft has confirmed that this is a problem in Microsoft Windows 2000. This problem was first corrected in Windows 2000 Service Pack 2.



MORE INFORMATION
For additional information about how to install Windows 2000 and Windows 2000 hotfixes at the same time, click the article number below to view the article in the Microsoft Knowledge Base:

249149 Installing Microsoft Windows 2000 and Windows 2000 Hotfixes

Keywords: kbhotfixserver kbqfe kbbug kbenv kbfix kbwin2000presp2fix KB273663

-

[mailto:TECHNET@MICROSOFT.COM Send feedback to Microsoft]

© Microsoft Corporation. All rights reserved.