Article ID: 241338 - View products that this article applies to.
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:
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.
Windows NT Server or Workstation 4.0To 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:
Windows NT Server 4.0, Terminal Server EditionTo resolve this problem, obtain the latest service pack for Windows NT Server 4.0, Terminal Server Edition. For additional information, click the following article number to view the article in the Microsoft Knowledge Base:
(https://support.microsoft.com/kb/152734/EN-US/ )How to Obtain the Latest Windows NT 4.0 Service Pack
Microsoft has confirmed that this is 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.
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:
147706This behavior may not occur when the following situations circumvent the issues involved:
(https://support.microsoft.com/kb/147706/EN-US/ )How to Disable LM Authentication on Windows NT
Article ID: 241338 - Last Review: June 19, 2014 - Revision: 4.0