DOCUMENT:Q178022 25-MAR-2002 [win95x] TITLE :NetBIOS SEND WAIT Over TCP/IP Completes Without NetBIOS RECEIVE PRODUCT :Microsoft Windows 95.x Retail Product PROD/VER::1,2,2.1 OPER/SYS: KEYWORDS:kbnetwork osr2 win95 kbAPI kbNetBIOS kbSDKPlatform kbGrpDSNet ====================================================================== ------------------------------------------------------------------------------- The information in this article applies to: - Microsoft Windows 95 - Microsoft Windows 95 OEM Service Release, versions 1, 2, 2.1 ------------------------------------------------------------------------------- SYMPTOMS ======== When a program issues a synchronous NetBIOS SEND (SEND_WAIT) command using Transmission Control Protocol/Internet Protocol (TCP/IP) on a Windows 95- based computer, the command immediately returns indicating successful completion, even if the computer to which the command is sent does not receive the data at the NetBIOS layer. Specifically, the SEND command may be completed even if the recipient does not post a NetBIOS RECEIVE Network Control Block (NCB). This may be a problem if the sending program terminates the session immediately after the synchronous SEND command is completed. If the recipient computer posts a NetBIOS RECEIVE NCB after it acknowledges the TCP/IP data, the sent data may no longer be available to be received. CAUSE ===== The Microsoft TCP/IP protocol included with Windows 95 acknowledges the receipt of NetBIOS data before the data is received at the NetBIOS layer, even if a NetBIOS RECEIVE NCB has not been posted. RESOLUTION ========== STATUS ====== This problem no longer occurs in Windows 98. To resolve this problem, install the current version of Windows. For information about the current version of Windows, visit http://www.microsoft.com/windows. MORE INFORMATION ================ This behavior is by design. However, the behavior of the NCBSENDWAIT command over TCP/IP is inconsistent with the behavior of the NCBSENDWAIT command over other protocols included with Windows 95 (such as Internetwork Packet Exchange/Sequenced Packet Exchange [IPX/SPX]- compatible protocol and NetBIOS Enhanced User Interface [NetBEUI] protocol). With other protocols, the NCBSENDWAIT command does not return until the recipient receives the data at the NetBIOS layer. This behavior may be undesirable if a program sends NetBIOS data, then terminates as soon as the SEND command is returned. Instead, if the program posts a NetBIOS RECEIVE command and waits for the recipient to complete the receive, this behavior has no adverse impact. Additional query words: ====================================================================== Keywords : kbnetwork osr2 win95 kbAPI kbNetBIOS kbSDKPlatform kbGrpDSNet Technology : kbWin95search kbOPKSearch kbZNotKeyword3 kbWin95OPKOSR2 kbWin95OPKOSR1 kbWin95OPKOSR210 Version : :1,2,2.1 ============================================================================= 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.