DOCUMENT:Q135679 08-AUG-2001 [winnt] TITLE :IGMP Group members Do Not Respond to IGMP Group Query Frames PRODUCT :Microsoft Windows NT PROD/VER: OPER/SYS: KEYWORDS: ====================================================================== ------------------------------------------------------------------------------- The information in this article applies to: - Microsoft Windows NT Workstation version 3.5 - Microsoft Windows NT Server version 3.5 ------------------------------------------------------------------------------- SYMPTOMS ======== Applications that use IGMP correctly add Windows NT computers to a multicast group, but do not maintain membership to the multicast group. CAUSE ===== Windows NT does not respond to the multicast group query frames sent by the router to verify that there are still members in the group. If there are no other computers capable of responding to group query on that segment, the group is be disabled. WORKAROUND ========== To work around this problem, place a computer running Windows NT 3.51 or Windows for Workgroups and Microsoft TCP/IP-32a for Windows for Workgroups, version 3.11b or later, on the same segment. This computer will handle the group queries. You can resolve the problem by upgrading the computer running Windows NT 3.5 to Windows NT 3.51. STATUS ====== Microsoft has confirmed this to be a problem in Windows NT version 3.5 This problem was corrected in Windows NT version 3.51. Additional query words: prodnt multi cast mcast ====================================================================== Keywords : Technology : kbWinNTsearch kbWinNTWsearch kbWinNT350search kbWinNTW350 kbWinNTW350search kbWinNTSsearch kbWinNTS350 kbWinNTS350search ============================================================================= 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.