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Q96830: Windows 3.0 Doesn’t Run in 386 Enhanced Mode

Article: Q96830
Product(s): Microsoft Disk Operating System
Version(s): MS-DOS:5.x,6.0,6.2,6.21; WINDOWS:3.0,3.0a
Operating System(s): 
Keyword(s): msdos
Last Modified: 17-DEC-2000

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

- Microsoft MS-DOS operating system versions 5.0, 5.0a, 6.0, 6.2, 6.21 
- Microsoft Windows versions 3.0, 3.0a 
-------------------------------------------------------------------------------

SUMMARY
=======

This article discusses how to correct the problem of Microsoft Windows version
3.0 not running in 386 enhanced mode on a system with Microsoft MS-DOS version
5.0 and later.

The article is divided into the following subsections:

- Extended Memory Requirements

- CONFIG.SYS File Requirements

- AUTOEXEC.BAT File Requirements

- WINA20.386 File Requirements

- Additional Steps for Systems Running EMM386.EXE

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

To ensure the Microsoft Windows version 3.0 can run on your system, make sure
your system meets all the requirements discussed in the following subsections.

Extended Memory Requirements
----------------------------

Your system must have at least 1 megabyte (MB) (1,048,576 bytes) of extended
memory. To determine the amount of available extended memory, type the following
at the MS-DOS command prompt, and press ENTER:

  " mem" (without the quotation marks)

If you do not have 1 MB of available extended memory, reduce your system's
extended memory usage by removing the DOS=HIGH command from your CONFIG.SYS
file. If you are using the version of SMARTDrive that is provided with MS-DOS
5.0 (SMARTDRV.SYS), reduce the value of the MinCacheSize parameter. If you are
using the version of SMARTDrive that is provided with MS-DOS version 6.0 or
later (SMARTDRV.EXE), reduce the value of the WinCacheSize parameter.

CONFIG.SYS File Requirements
----------------------------

By default, Setup configures MS-DOS to install HIMEM.SYS when you start your
system. If MS-DOS does not install HIMEM.SYS, make sure the the following
command appears in your CONFIG.SYS file before any commands that start device
drivers or programs that use extended memory:

  device=c:\dos\himem.sys

In addition, verify the following in your CONFIG.SYS file:

- The FILES command must specify at least 30 files.

- The BUFFERS command must specify at least 20 buffers.

AUTOEXEC.BAT File Requirements
------------------------------

Your AUTOEXEC.BAT file must include a SET command such as the following that
establishes the location where temporary files are stored:

  set temp=<drive>:\<directory>

where <drive> is your hard disk drive and <directory> is the
directory where your temporary files are stored. This set command creates an
environment variable that Windows version 3.0 uses to determine where to store
its temporary files. For example, the following command directs Windows to store
its temporary files in a directory named TEMP on drive C:

  set temp=c:\temp

WINA20.386 File Requirements
----------------------------

Your system must include the WINA20.386 file. The Setup program for MS-DOS places
this file in the root directory of your startup drive (usually drive C). If you
have moved the WINA20.386 file to another directory, you need to edit your
CONFIG.SYS and SYSTEM.INI files to reflect the accurate location of this file.
Use the procedures outlined below.

If you can't find the WINA20.386 file in any directory on your hard disk drive,
expand and copy the file from your MS-DOS installation disks to the root
directory of your startup drive by typing the following at the MS-DOS command
prompt and pressing ENTER

  expand <floppy>:\wina20.38_ <startupdrive>:\wina20.386

where <floppy> is the floppy disk drive that contains the installation disk
with the compressed file you want to expand, and <startupdrive> is your
startup drive. For example, if your installation disk is in floppy disk drive A
and your startup drive is drive C, type the following command:

  " expand a:\wina20.38_ c:\wina20.386" (without the quotation marks)

The WINA20.386 file is located on the following installation disks:

   MS-DOS       3.5-Inch Disk  5.25-Inch    3.5-Inch   5.25-Inch
   Version      Number (1.44   Disk Number  Disk       Disk
                MB)            (1.2 MB)     Number     Number
                                            (720K)     (360K)
   -------------------------------------------------------------

   MS-DOS 5     N/A            N/A          Disk 3     Disk 5
   Upgrade
   MS-DOS 5.0a  N/A            Disk 2       Disk 3     Disk 5
   Upgrade
   MS-DOS 6.0   Disk 1         Disk 2       Disk 3     Disk 5
   Upgrade
   MS-DOS 6.2   Disk 1         Disk 2       Disk 3     Disk 5
   Upgrade
   MS-DOS 6.21  Disk 1         Disk 2       Disk 3     Disk 5
   Upgrade

If you have moved your WINA20.386 file to a directory other than the root
directory of your startup drive, use the following procedure to allow Windows
3.0 to find it:

1. Edit your CONFIG.SYS file. To edit the file using MS-DOS Editor, type the
  following at the MS-DOS command prompt and press ENTER:

  " edit <startupdrive>:\config.sys" (without the quotation marks)

2. Add the following line at the end of your CONFIG.SYS file:

  switches=/w

3. Save your CONFIG.SYS file. If you're using MS-DOS Editor, choose Exit from
  the File menu. When MS-DOS Editor displays a dialog box prompting you to save
  your file, choose the Yes button or press ENTER.

4. Next, use MS-DOS Editor to open your Windows SYSTEM.INI file. Your SYSTEM.INI
  file is in the directory where your Windows files reside. To edit the file,
  type the following at the MS-DOS command prompt and then press ENTER:

  " edit <drive>:\<directory>\system.ini" (without the quotation
  marks)

  where <drive> is your hard disk drive and <directory> is the
  directory where your Windows files reside. For example, if your hard disk
  drive is drive C and your Windows files are located in the WINDOWS directory,
  type the following command:

  " edit c:\windows\system.ini" (without the quotation marks)

5. Locate the section of your SYSTEM.INI file that begins with the [386Enh]
  heading, and add the following command:

  " device=<drive>:\<directory>\wina20.386" (without the quotation
  marks)

  where <drive> is your hard disk drive and <directory> is the
  directory where the WINA20.386 file is now located. For example, if you moved
  the file to your WINDOWS directory, you would add the following command to
  your Windows SYSTEM.INI file:

  " device=c:\windows\wina20.386" (without the quotation marks)

6. Save your SYSTEM.INI file. If you're using MS-DOS Editor, choose Exit from
  the File menu. When MS-DOS Editor displays a dialog box prompting you to save
  your file, choose the Yes button or press ENTER.

7. Restart your computer by pressing CTRL+ALT+DEL.

Additional Steps for Systems Running EMM386.EXE
-----------------------------------------------

If Windows version 3.0 doesn't run in 386 enhanced mode after you have checked
the items listed above, and you are using EMM386.EXE, do the following:

1. Use a text editor, such as MS-DOS Editor, to open the SYSTEM.INI file that is
  located in the directory where your Windows files reside. If you want to use
  MS-DOS Editor, type the following at the MS-DOS command prompt and press
  ENTER

  " edit <drive>:\<directory>\system.ini" (without the quotation
  marks)

  where <drive> is your hard disk drive and <directory> is the
  directory where your Windows files reside. For example, if your hard disk
  drive is drive C and your Windows files are located in the WINDOWS directory,
  type the following command:

  " edit c:\windows\system.ini" (without the quotation marks)

2. Insert the following command in the [386Enh] section of the SYSTEM.INI file:

  " EMMEXCLUDE=A000-EFFF" (without the quotation marks)

3. Save your SYSTEM.INI file. If you're using MS-DOS Editor, choose Exit from
  the File menu. When MS-DOS Editor displays a dialog box prompting you to save
  your file, choose the Yes button or press ENTER.

4. Start Windows version 3.0. If Windows version 3.0 does not run in 386
  enhanced mode, a device conflict is preventing Windows from running in 386
  enhanced mode. Call Microsoft Product Support Services for help.


Additional query words: appnote 6.00 5.00 6.20 win30 enh enhanced-mode

======================================================================
Keywords          : msdos 
Technology        : kbWin3xSearch kbZNotKeyword3 kbWin300 kbWin300a kbMSDOSSearch kbMSDOS621 kbMSDOS620 kbMSDOS600 kbMSDOS500 kbMSDOS500a
Version           : MS-DOS:5.x,6.0,6.2,6.21; WINDOWS:3.0,3.0a

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

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