DOCUMENT:Q159500 22-FEB-2002 [winnt] TITLE :Using DLC and IPX Protocols May Corrupt Incoming Packets PRODUCT :Microsoft Windows NT PROD/VER::3.51 OPER/SYS: KEYWORDS:kbenv kbinterop kbnetwork ====================================================================== ------------------------------------------------------------------------------- The information in this article applies to: - Microsoft Windows NT Server version 3.51 ------------------------------------------------------------------------------- SYMPTOMS ======== When you use DLC and NWLINK protocols on Windows NT Server version 3.51, incoming DLC packets may become corrupted. The problem was observed on a multiprocessor IBM 720 computer with an IBM PCI ETHERNET adapter running Windows NT Server version 3.51 Service Pack 4, SNA Server and SMS 1.1. CAUSE ===== In this case, SMS was generating local traffic (sending and receiving frames to itself) using UNC name over NWlink protocol. NWLink depends on the NDIS Wrapper or the NDIS MAC driver to provide loopback functionality. Consequently, frames are sent out on the wire and then received back in. Occasionally, under stress, incoming DLC frames were getting corrupted by the loopback nwlink data frames. RESOLUTION ========== To work around this problem, install another protocol (TCP/IP or NetBEUI) using the Control Panel Network tool and make sure that NWLink is not the first protocol to bind to the Workstation service. STATUS ====== Microsoft has confirmed this to be a problem in Windows NT version 3.51. We are researching this problem and will post new information here in the Microsoft Knowledge Base as it becomes available. Additional query words: ipx ====================================================================== Keywords : kbenv kbinterop kbnetwork Technology : kbWinNTsearch kbWinNT351search kbWinNTSsearch kbWinNTS351 kbWinNTS351search Version : :3.51 Issue type : kbbug ============================================================================= 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.