DOCUMENT:Q73829  17-DEC-2000  [msdos]
TITLE   :Windows/386 2.1x Compatibility with MS-DOS 5.0 or Later
PRODUCT :Microsoft Disk Operating System
PROD/VER:MS-DOS:5.x,6.0
OPER/SYS:
KEYWORDS:

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The information in this article applies to:

 - Microsoft MS-DOS operating system versions 5.0, 5.0a, 6.0 
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SUMMARY
=======

Windows 386 versions 2.1 and 2.11 cannot run when EMM386.EXE from MS-DOS 5.0 or
later is loaded in the CONFIG.SYS file. Attempting to use this configuration
results in the following error message:

   Error: Protected mode software already installed

This problem occurs regardless of which switches are used with EMM386.EXE. To run
Windows/386 2.1x, you cannot use EMM386.EXE to emulate expanded memory or load
drivers high.

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

Other device drivers from the Microsoft MS-DOS 5.0 Upgrade to be aware of are
listed in the README.TXT file section 4.5.

The following is an excerpt from the README.TXT file:

4.5 "High Memory Area in Use" Message (Windows/386 2.1)
-------------------------------------------------------

You cannot run Windows/386 2.1 when MS-DOS 5.0 is loaded into the high memory
area. Also, the MS-DOS 5.0 versions of SMARTDRV.SYS and RAMDRIVE.SYS are not
compatible with Windows/386 2.1. To run Windows/386 2.1 with MS-DOS 5.0, use the
versions of SMARTDRV.SYS and RAMDRIVE.SYS that came with Windows and remove the
DOS=HIGH command, if any, from your CONFIG.SYS file.

Additional query words: 5.00 5.00a 6.00 noupd

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Keywords          :  
Technology        : kbMSDOSSearch kbMSDOS600 kbMSDOS500 kbMSDOS500a
Version           : MS-DOS:5.x,6.0

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