DOCUMENT:Q230204 08-MAY-2002 [sna] TITLE :SNA Server Fails Due to Access Violation in SNADMOD!RpcRouteProc PRODUCT :Microsoft SNA Server PROD/VER:WINDOWS:3.0,3.0SP1,3.0SP2,3.0SP3,4.0,4.0SP1,4.0SP2 OPER/SYS: KEYWORDS:kbsna400sp3fix ====================================================================== ------------------------------------------------------------------------------- The information in this article applies to: - Microsoft SNA Server, versions 3.0, 3.0SP1, 3.0SP2, 3.0SP3, 4.0, 4.0SP1, 4.0SP2 ------------------------------------------------------------------------------- SYMPTOMS ======== The SNA Server service (Snaservr.exe) may fail unexpectedly or may stop accepting new client connections when the access violation in SNADMOD!RpcRoutProc occurs. This results in one or both of the following: - Previously-connected users lose their host (mainframe or AS/400) sessions. - New users are unable to obtain a new host session. If the Windows NT Server where SNA Server is running is configured with Drwtsn32.exe as the default debugger, a Drwtsn32.log entry may be generated when this failure occurs, indicating a FAULT in the top-level routine along with the following stack-back trace (which may vary): snadmod!RpcRouteProc+0x400 snadmod!sepdq2_int+0x122 ntdll!RtlLeaveCriticalSection+0x1d snadmod!sbpdin_int+0x23d snadmod!sbpdin+0x25 snaservr!sbpcdin+0x50 snaservr!sbpsched+0x2ac snaservr!sbpgmain+0x25 snasvc!ServiceMainFunction+0x140 advapi32!ScSvcctrlThreadA+0xe kernel32!BaseThreadStart+0x51 In the reported instances of this problem, the SNA Server systems had to be rebooted to recover. CAUSE ===== The access violation occurs when an SNA Server RPC Response message is inadvertently routed to the SNA Server service. The SNA Server service is unable to interpret this message, which causes the access violation to occur. RESOLUTION ========== SNA Server 4.0 -------------- To resolve this problem, obtain the latest service pack for SNA Server version 4.0. For additional information, please see the following article in the Microsoft Knowledge Base: Q215838 How to Obtain the Latest SNA Server Version 4.0 Service Pack SNA Server 3.0 -------------- A supported fix is now available from Microsoft, but it is only intended to correct the problem described in this article and should be applied only to systems experiencing this specific problem. To resolve this problem, contact Microsoft Product Support Services to obtain the fix. 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 NOTE: In special cases, charges that are normally incurred for support calls may be canceled, if a Microsoft Support Professional determines that a specific update will resolve your problem. Normal support costs will apply to additional support questions and issues that do not qualify for the specific update in question. The English version of this fix should have the following file attributes or later: +---------------------------------+ | File name | Date | Time | +---------------------------------+ | Snadmod.dll | 3/11/99 | 7:45PM | +---------------------------------+ | snaevent.dll | 3/11/99 | 7:46PM | +---------------------------------+ NOTE: Because of file dependencies, the most recent fix that contains the above files may also contain additional files. STATUS ====== Microsoft has confirmed this to be a problem in Microsoft SNA Server versions 3.0, 3.0 SP1, 3.0 SP2, 3.0 SP3, 4.0, 4.0 SP1, and 4.0 SP2. This problem was first corrected in SNA Server version 4.0 Service Pack 3. MORE INFORMATION ================ An exception handler was added to handle this exception whenever it may occur. The SNA Server service will no longer fail unexpectedly or stop accepting client connections when this occurs after the update is applied. In addition, the following event will be logged in the Windows NT application event log if this problem occurs after the update is applied. Event ID: 731 Description: Invalid RPC Response message RPC Code: Source: Destination: Additional query words: ====================================================================== Keywords : kbsna400sp3fix Technology : kbAudDeveloper kbSNAServSearch kbSNAServ300 kbSNAServ400 Version : WINDOWS:3.0,3.0SP1,3.0SP2,3.0SP3,4.0,4.0SP1,4.0SP2 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.