SNA Client or DLS Cannot Connect as Guest User on Windows 2000 (264082)

SYMPTOMS

If an SNA Windows NT client attempts to connect to an SNA Server that is running on a non-trusted Windows 2000 Server-based computer with the Guest account enabled, the SNA client fails to connect, and you receive the following error message:

ERROR #1003
SnaBase could not open a sponsor connection to server [Servername]

However, if an SNA Windows 95 or Windows 98 client is used, and the Guest account is explicitly used on the same non-trusted Windows 2000 Server-based computer, the connection succeeds.

If an SNA Server Distributed Link Service (for example, SnaRem1) attempts to connect through an SNA Server link service that is running on a non-trusted Windows 2000 Server-based computer, the connection may stay in a pending state, and the following event is logged:

Event ID: 705
Source: SNA DLC Link Service
Description: Logon Failed
EXPLANATION
Connection request failed due to data security.
Access denied -- Error Code: 43

On the Windows 2000-based computer, the SnaBase Service logs the following event whenever the Distributed Link Service attempts to connect (approximately every 10-20 seconds):

Event ID: 705
Source: SNA Base Service
Description: Logon Failed.
EXPLANATION
Access denied on client-server or Distributed Link Service connection request.

Unknown user name or bad password from client [computername] --- Error Code : 4097

ACTION
Contact your network support personnel.

CAUSE

Windows 2000 implements stricter Windows NT Challenge/Response (NTLM) security during client logon than Windows NT 4.0, which prevents failover to the Guest account if the ISC_REQ_INTEGRITY option is requested during the Security Support Provider Interface (SSPI) logon process. Because the SNA client requests this option, a non-trusted user's NTLM logon fails on Windows 2000 even when the Guest account is enabled. However, if the Guest account is explicitly specified (by using the SNA Windows 95 or Windows 98 client Advanced options, which are not available in the SNA Windows NT client), the logon succeeds because it is clear that Guest access is being requested.

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

To work around the problem, the SNA client or Distributed Link Service must use a user account and password that exists in the target Windows 2000 domain. Or, if you are using the SNA Windows 95 or Windows 98 client, you can configure the client to connect explicitly as the Guest user.

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 2. The English version of this fix should have the following file attributes or later:

   Date       Time    Size          File name
   -------------------------------------------
   7/21/2000  09:02a  99,792 bytes  msv1_0.dll