DOCUMENT:Q175271 13-JUN-2001 [sna] TITLE :SNA 3.0 SP2 Hang or Access Violation in SNA Server or SnaBase PRODUCT :Microsoft SNA Server PROD/VER:WINDOWS:3.0 SP2 OPER/SYS: KEYWORDS: ====================================================================== ------------------------------------------------------------------------------- The information in this article applies to: - Microsoft SNA Server, version 3.0 SP2 ------------------------------------------------------------------------------- SYMPTOMS ======== After you upgrade to Microsoft SNA Server 3.0 Service Pack 2, one of the following symptoms may occur while the server is running: - Users who have active sessions may find their computer suddenly hangs or stops responding (3270 users may receive perpetual XCLOCK), and new user connection attempts to either the SnaBase or SNA Server service may fail. - The SnaBase or SNA Server service may terminate unexpectedly with the following error messages: Windows NT application event log error: Event: 624 Source: SNA Server (or SnaBase) Description: Creating dump file C:\SNA\traces\snadump.log for Snaservr.exe [or snabase.exe] Also, an \Drwtsn32.log entry may be created, indicating the following failure: Application exception occurred: App: snaservr.DBG (pid=) When: Exception number: c0000005 (access violation) The fault entry indicated in routine ntdll!RtlAllocateHeap, or ntdll!RtlDestroyHeap. CAUSE ===== In SNA Server 3.0 Service Pack 2, client logon requests are now handled from multiple threads within the SnaBase or SNA Server service. If two concurrent client logon requests occur that both use the LSA authentication method (that is, Windows 3.x clients, or Windows NT services that run under the local system account), the SnaBase or SNA Server memory heap may become corrupted. This occurs because LSA logon is not thread-safe, so two concurrent LSA logon requests from the same process can result in memory corruption. STATUS ====== Microsoft has confirmed this to be a problem in SNA Server version 3.0 Service Pack 2. This problem was corrected in the latest SNA Server version 3.0 U.S. Service Pack. For information on obtaining this Service Pack, query on the following word in the Microsoft Knowledge Base (without the spaces): S E R V P A C K Additional query words: ====================================================================== Keywords : Technology : kbAudDeveloper kbSNAServSearch kbSNAServ300SP2 Version : WINDOWS:3.0 SP2 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 2001.