Authentication May Fail for Users Without a Windows NT Password Hash (312035)


The information in this article applies to:

  • Microsoft Windows 2000 Server SP2
  • Microsoft Windows 2000 Advanced Server SP2
  • Microsoft Windows 2000 Professional SP2
  • Microsoft Windows NT Workstation 4.0 SP6a
This article was previously published under Q312035

SYMPTOMS

When a user account only has an LM hash and not a Windows NT hash, authentication may fail as it would when a bad password is used. This happens only when the user's password was changed so that only the LM hash was updated. This problem only exists on Windows 2000 Service Pack 2 (SP2) and Windows NT 4.0 post Service Pack 6 (SP6) SRP, or one of these operating systems with certain hotfixes in place for the Advapi32.dll file.

CAUSE

This problem can occur when LogonUser is called.

RESOLUTION

Windows 2000

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
   --------------------------------------------------------
   13-Nov-2001  11:48  5.0.2195.4622  356,112  Advapi32.dll
   13-Nov-2001  11:48  5.0.2195.4571   82,704  Cmnquery.dll
   13-Nov-2001  11:48  5.0.2195.4534   41,744  Dsfolder.dll
   13-Nov-2001  11:48  5.0.2195.4534  156,944  Dsquery.dll
   13-Nov-2001  11:48  5.0.2195.4574  110,352  Dsuiext.dll

Windows NT 4.0 SP6a Computers with the SRP Installed

The English version of this fix should have the following file attributes or later:
   Date         Time   Version           Size     File name
   -----------------------------------------------------------
   05-Dec-2001  17:15  4.0.1381.7114     248,592  Advapi32.dll
NOTE: Due to file dependencies, this hotfix requires Microsoft Windows NT 4.0 Service Pack 6a.

WORKAROUND

To work around this problem, note that you can change the user's password from a Windows-based client to properly update the hashes.

STATUS

Microsoft has confirmed that this is a problem in the Microsoft products that are listed at the beginning of this article. This problem was first corrected in Windows 2000 Service Pack 3.

MORE INFORMATION

The hotfix that is described in this article updates the LogonUser function.

For additional information about how to obtain a hotfix for Windows 2000 Datacenter Server, click the article number below to view the article in the Microsoft Knowledge Base:

265173 The Datacenter Program and Windows 2000 Datacenter Server Product

For additional information about how to install multiple hotfixes with only one reboot, click the article number below to view the article in the Microsoft Knowledge Base:

296861 Use QChain.exe to Install Multiple Hotfixes with One Reboot

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

Modification Type:MinorLast Reviewed:9/26/2005
Keywords:kbHotfixServer kbQFE kbbug kbenv kbfix kbSecurity kbWin2000PreSP3Fix kbWin2000sp3fix KB312035
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