DOCUMENT:Q126429 08-AUG-2001 [winnt] TITLE :Win16 Subsystem Fails When Used with Equinox Serial Driver PRODUCT :Microsoft Windows NT PROD/VER:3.50 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 ======== When using Equinox Systems intelligent serial board and driver, the Win16 subsystem fails when a 16-bit terminal application is run. Example programs of this type are WinCim and Procomm Plus for Windows. The following message may appear: Application caused an exception in the Win16 subsystem Then, the 16-bit application and the Win16 subsystem terminate. However, Windows NT does not fail. CAUSE ===== The Win16 subsystem is not correctly dealing with overlapped reads when communicating with the COM ports. When a ReadFile is issued, the Win16 subsystem assumes it either has completed immediately or that it has failed (that is, it assumes that the read is synchronous). When using the Equinox serial driver, the Win16 subsystem assumes all the reads are failing because none of the reads are completed immediately. This situation eventually causes the Win16 subsystem to fail. STATUS ====== Microsoft has confirmed this to be a problem in Windows NT Workstation and Windows NT Server version 3.5. This problem was corrected in the latest U.S. Service Pack for Windows NT version 3.5. 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 The products included here are manufactured by vendors independent of Microsoft; we make no warranty, implied or otherwise, regarding these products' performance or reliability. Additional query words: prodnt ====================================================================== Keywords : Technology : kbWinNTsearch kbWinNTWsearch kbWinNT350search kbWinNTW350 kbWinNTW350search kbWinNTSsearch kbWinNTS350 kbWinNTS350search Version : 3.50 ============================================================================= 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.