======================================================================
  Microsoft(R) Product Support Services Application Note (Text File)
   WG1001: UPDATED SERIAL.386 DRIVER FOR WINDOWS(TM) FOR WORKGROUPS
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                                                   Revision Date: 3/94
                                                       1 Disk Included

The following information applies to Microsoft Windows for Workgroups,
version 3.11.

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| Copyright (C) 1994 Microsoft Corporation.  All Rights Reserved.     |
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Introduction
------------

When you use Windows for Workgroups version 3.11 with serial
communications software, you may experience the following problems:

 - If you are using a Pentium(TM)-based machine with a 16550 UART chip,
   your system stops responding (hangs) if there is data in the chip
   when the serial communications application attempts to open the
   communications port.
   
   A problem with the 16550 UART implementation causes the chip to
   become trapped in a mode in which data is always detected in its
   FIFO buffer.

 - When you are using communications software, you may be able to make
   one connection after starting Windows for Workgroups, but any
   subsequent connections fail and may hang your system.
   
   This problem occurs when SERIAL.386 sends an extra NUL character
   through the port when the communications software calls the
   CloseComm application program interface (API) function. While this
   does not normally cause problems, your second connection may fail
   with some modems.

The WG1001 disk included with this Application Note contains an
updated SERIAL.386 driver that corrects both of these problems.

To install the updated SERIAL.386 file
--------------------------------------

1. Quit Windows for Workgroups.

2. Make a backup copy of the currently installed SERIAL.386 file by
   typing the following at the MS-DOS command prompt and then pressing
   ENTER

      ren <drive>:<path>\serial.386 serial.old

   where <drive>:<path> is the location of your Windows SYSTEM
   subdirectory.

   For example, if your Windows directory is called WINDOWS and is on
   drive C, type the following at the MS-DOS command prompt and then
   press ENTER:

      ren c:\windows\system\serial.386 serial.old

3. Insert the enclosed WG1001 disk in the appropriate floppy disk
   drive.

4. To copy the file to the Windows SYSTEM subdirectory, type the
   following at the MS-DOS command prompt and then press ENTER

      copy <drive>:\serial.386 <destination>

   where <drive> is the floppy disk drive containing the WG1001 disk
   and <destination> is the drive and directory of your Windows SYSTEM
   subdirectory.

   For example, if the WG1001 disk is in drive A and your Windows
   directory is called WINDOWS and is on drive C, type the following
   at the MS-DOS command prompt and then press ENTER:

      copy a:\serial.386 c:\windows\system