DOCUMENT:Q94682  02-OCT-1999  [win95x]
TITLE   :Windows 3.1 COMM.DRV File May Be Incompatible with PS/2 50Z
PRODUCT :Microsoft Windows 95.x Retail Product
PROD/VER:WINDOWS:3.1,3.11
OPER/SYS:
KEYWORDS:win31

======================================================================
-------------------------------------------------------------------------------
The information in this article applies to:

 - Microsoft Windows versions 3.1, 3.11 
-------------------------------------------------------------------------------

SUMMARY
=======

The Windows 3.1 COMM.DRV designed for external modems that are connected to the
on board serial port (COM1) may not work with early models of the IBM PS/2 50Z.
Windows may not be able to communicate with the modem, or the computer may lock
up.

The following information does not apply to internal modems because they do not
use the external serial port on the 50Z. They should work with Windows 3.1.

MORE INFORMATION
================

Early versions of the IBM PS/2 model 50Z may have shipped with ZM41 system
boards that use a non-standard serial communications port.

At speeds less than 9600bps, the external (COM1) serial port may fail with
Windows 3.1 and other communications programs, including Autosig for MS-DOS and
the CompuServe Information Manager (CIM) for MS-DOS.


WORKAROUND
==========

As a possible workaround, you can try using the COMM.DRV driver for Windows 3.0.
If you have this driver available, install it as follows:

1. Make a backup copy of the COMM.DRV that is located in your Windows system
   subdirectory.

2. Insert the Windows 3.0 disk that contains COMM.DR_ into a floppy disk drive.
   This file is located on disk 1 (5.25-inch high-density), disk 2 (3.5-inch
   low-density) or disk 4 (5.25-inch low-density).

3. Use the EXPAND command to expand the file to the hard disk. For example:

   EXPAND A:COMM.DR_ c:\Windows\SYSTEM

For further information, please contact IBM.


The IBM products included here are manufactured by International Business
Machines, Inc., a vendor independent of Microsoft; we make no warranty, implied
or otherwise, regarding these products' performance or reliability.

KBCategory: kb3rdparty kbprb
KBSubcategory: wwin31 wincom

Additional query words: 3.10 8550 8550z hang

======================================================================
Keywords          : win31 
Technology        : kbWin3xSearch kbZNotKeyword3 kbWin310 kbWin311
Version           : WINDOWS:3.1,3.11

=============================================================================

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 1999.