DOCUMENT:Q139785 13-JUN-2001 [sna] TITLE :RUI Problem Handling RUI_SEND After Sense Data Received PRODUCT :Microsoft SNA Server PROD/VER:WINDOWS:2.1,2.11 OPER/SYS: KEYWORDS: ====================================================================== ------------------------------------------------------------------------------- The information in this article applies to: - Microsoft SNA Server, versions 2.1, 2.11 ------------------------------------------------------------------------------- SYMPTOMS ======== If the host application sends sense data to an RUI application while the RUI application is sending data, the SNA Server RUI library queues the application data in error and never sends it, causing the RUI application and the host application to become unsynchronized. CAUSE ===== The RUI application gets the sense data indicator (SDI) message and correctly sends negative response. Because the RUI library is in the middle of a chain (it has only received Begin Chain - BCI, not End Chain - ECI) it sets a flag telling it to discard all data messages until it receives one with ECI set. Unfortunately the server performs the same check. Therefore the RUI library does not see the ECI flag until it receives the end of the NEXT chain (the retried one). RESOLUTION ========== The RUI application can't work around this problem. The solution is for the RUI library to detect that a new chain is starting without the purging one ending, and simply to stop purging at that point. An update to the SNA Server RUI DLL corrects this problem. Note that with this update applied, the RUI application will still miss the Middle of Chain (MC) and EC sequence numbers on the rejected chain. Microsoft has updated the following files to correct this problem: Client Platforms Updated Files ----------------------------------------------------------- Win32 \system\WINRUI32.DLL Windows 3.x \system\WINRUI.DLL OS/2 \ACSRUI.DLL STATUS ====== Microsoft has confirmed this to be a problem in SNA Server for Windows NT. This problem was corrected in the latest SNA Server for Windows NT, 2.11 U.S. Service Pack. For information on obtaining the 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: prodsna 2.10 2.11 ====================================================================== Keywords : Technology : kbAudDeveloper kbSNAServSearch kbSNAServ211 kbSNAServ210 Version : WINDOWS:2.1,2.11 ============================================================================= 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.