DOCUMENT:Q241338 20-MAY-2002 [winnt] TITLE :Windows NT Lan Manager 3 Logon Prevents Other Logon Activity PRODUCT :Microsoft Windows NT PROD/VER:winnt:4.0 OPER/SYS: KEYWORDS:kberrmsg kbnetwork kbWinNT4sp6fix ====================================================================== ------------------------------------------------------------------------------- The information in this article applies to: - Microsoft Windows NT Server version 4.0, Terminal Server Edition - Microsoft Windows NT Server version 4.0 - Microsoft Windows NT Workstation version 4.0 - Microsoft Windows NT Server, Enterprise Edition version 4.0 ------------------------------------------------------------------------------- SYMPTOMS ======== When a client uses Windows NT LAN Manager version 2 authentication (also known as NTLMv2) that is configured with the LmCompatibilityLevel setting to 3 or higher to make a connection to a server running Windows NT 4.0 before a console user has logged on interactively or some other client has performed network logon using LAN Manager or NTLMv1 authentication, one of the following symptoms may occur on the server: - The server may generate an "access violation" error message, possibly relating to the LSASS service. This may occur on both the server and the client during startup, especially during periods of heavy network logon traffic. - The domain name field may not appear on the logon screen of the server even though the user name and password fields do. You may not be able to log on to the domain because this indicates that the domain controller cannot be found. - Your logon attempt may not work, and you may receive the following error message: The system cannot log you on (C0000037). Please try again or consult your system administrator. CAUSE ===== This behavior occurs because the Windows NT LAN Manager version 2 (level 3+) logon is received and processed by the server before the NlSamInitialize function is called, causing an "Access violation" error message. Also, at this time Lsass.exe generates a "STATUS_PORT_DISCONNECTED" error message, which prevents subsequent logon attempts from succeeding. RESOLUTION ========== Windows NT Server or Workstation 4.0 ------------------------------------ To resolve this problem, obtain the latest service pack for Windows NT 4.0 or the individual software update. For information on obtaining the latest service pack, please go to: - http://www.microsoft.com/Windows/ServicePacks/ -or- - Q152734 How to Obtain the Latest Windows NT 4.0 Service Pack For information on obtaining the individual software update, contact Microsoft Product Support Services. For a complete list of Microsoft Product Support Services phone numbers and information on support costs, please go to the following address on the World Wide Web: http://support.microsoft.com/default.aspx?scid=fh;EN-US;CNTACTMS Windows NT Server 4.0, Terminal Server Edition ---------------------------------------------- To resolve this problem, obtain the latest service pack for Windows NT Server 4.0, Terminal Server Edition. For additional information, please see the following article in the Microsoft Knowledge Base: Q152734 How to Obtain the Latest Windows NT 4.0 Service Pack STATUS ====== Microsoft has confirmed this to be a problem in Windows NT 4.0 and Windows NT Server 4.0, Terminal Server Edition. This problem was first corrected in Windows NT Server 4.0 Service Pack 6 and Windows NT Server 4.0, Terminal Server Edition Service Pack 6. MORE INFORMATION ================ Windows NT 4.0 supports Windows NT challenge/response (or Windows NT LAN Manager challenge/response) as a method of authentication, along with Basic Authentication and Anonymous Access. Microsoft has developed an enhancement to NTLM called Windows NT LAN Manager version 2 which uses a 128-bit password-derived key and significantly improves session security mechanisms. For more information about Windows NT LAN Manager version 2, please click the article number below to view the article in the Microsoft Knowledge Base: Q147706 How to Disable LM Authentication on Windows NT This behavior may not occur when the following situations circumvent the issues involved: - When a server service that runs using a user account starts before the first non-anonymous logon. - When a user interactively logs on to the server console before the first non-anonymous logon occurred. - When a client computer is not configured to send Windows NT LAN Manager version 2 only (level 3) as the first non-anonymous logon Additional query words: ntlmv2 ntlm invalid handle invalid_handle 6 ====================================================================== Keywords : kberrmsg kbnetwork kbWinNT4sp6fix Technology : kbWinNTsearch kbWinNTWsearch kbWinNTW400 kbWinNTW400search kbWinNT400search kbWinNTSsearch kbWinNTSEntSearch kbWinNTSEnt400 kbWinNTS400search kbWinNTS400 kbNTTermServ400 kbNTTermServSearch Version : winnt:4.0 Issue type : kbbug Solution Type : kbfix ============================================================================= THE INFORMATION PROVIDED IN THE MICROSOFT KNOWLEDGE BASE IS PROVIDED "AS IS" WITHOUT WARRANTY OF ANY KIND. MICROSOFT DISCLAIMS ALL WARRANTIES, EITHER EXPRESS OR IMPLIED, INCLUDING THE WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. IN NO EVENT SHALL MICROSOFT CORPORATION OR ITS SUPPLIERS BE LIABLE FOR ANY DAMAGES WHATSOEVER INCLUDING DIRECT, INDIRECT, INCIDENTAL, CONSEQUENTIAL, LOSS OF BUSINESS PROFITS OR SPECIAL DAMAGES, EVEN IF MICROSOFT CORPORATION OR ITS SUPPLIERS HAVE BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGES. SOME STATES DO NOT ALLOW THE EXCLUSION OR LIMITATION OF LIABILITY FOR CONSEQUENTIAL OR INCIDENTAL DAMAGES SO THE FOREGOING LIMITATION MAY NOT APPLY. Copyright Microsoft Corporation 2002.