Please note: The following document is taken from the Microsoft Knowledge Base.
You can access the Knowledge Base on the Web at:

http://www.microsoft.com/kb/default.asp

======================================================================
  Microsoft(R) Product Support Services Application Note (Text File)
              WW0524: Troubleshooting GP Faults (UAEs)
======================================================================
                                                   Revision Date: 8/94
                                                      No Disk Included

The following information applies to Windows(TM) & Windows for 
Workgroups, versions 3.0, 3.1, and 3.11.

----------------------------------------------------------------------
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|--------------------------------------------------------------------|

INTRODUCTION
============

This document describes general protection (GP) faults (referred 
to as unrecoverable application errors [UAEs] in Windows 3.0), 
details the causes of these errors, and provides a systematic 
approach to eliminate them.

WHAT IS A GENERAL PROTECTION (GP) FAULT?
========================================

GP faults occur only in the standard and 386 enhanced modes of 
Windows; they cannot occur in the real mode of Windows 3.0. A GP 
fault signifies that something unexpected has happened within the 
Windows environment, typically an improper memory access. For 
example, an application or a Windows component might read or write 
to a memory location that has not been allocated to it (memory 
that it does not "own"), potentially overwriting and corrupting 
other program code in that area of memory.

Another situation where a GP fault may occur involves the passing 
of parameters between applications and the Windows environment. 
Invalid parameters can cause invalid instructions to be executed, 
resulting in GP faults. This is usually the result of an 
application's internal program code incorrectly passing specific 
data that could not be correctly interpreted by Windows or a 
Windows-based application.

What Is a System Integrity Violation?
-------------------------------------

A system integrity violation error message indicates that an MS-
DOS-based application has caused a GP fault. Similar to a GP 
fault, system integrity violations indicate that an MS-DOS-based 
application has accessed memory that does not belong to it. 
Because Windows is managing memory in this situation, the MS-DOS-
based application's memory access often corrupts Windows program 
code or data. The result is an application execution error 
generated from Windows that reports the "application has violated 
system integrity due to an invalid general protection fault and 
will be terminated." This message can also occur when an MS-DOS-
based application has tried to directly access a hardware 
component of the system.

HOW DO WINDOWS 3.1 AND WINDOWS FOR
WORKGROUPS 3.1 AND 3.11 HANDLE GP FAULTS?
=========================================

The parameter validation feature allows Windows 3.1 and both 
versions of Windows for Workgroups to check for invalid parameters 
passed between Windows and Windows-based applications. Windows 3.1 
and Windows for Workgroups are also designed to better manage and 
maintain which applications "own" specific memory locations and 
system resources. As a result, Windows 3.1 and Windows for 
Workgroups are better at recovering a particular application's 
memory and system resources if the application causes a GP fault 
and subsequently stops responding (hangs).

When you see a GP fault message while running Windows 3.1 or 
Windows for Workgroups, the message provides specific information 
about which applications and Windows components were running at 
the time of the error, and where the error occurred. If the GP 
fault is not too severe, Windows can continue to run the 
application that caused the fault, allowing you to save your work 
before you close the application.

Performing a Local Reboot
-------------------------

Depending on the severity of a GP fault in Windows 3.1 or Windows 
for Workgroups, you may be able to press CTRL+ALT+DEL to display 
information concerning system integrity and the application that 
caused the fault. The severity of a GP fault can be measured by 
how well an application functions after the fault has occurred. 
When you press CTRL+ALT+DEL after a less severe fault occurs, the 
following message appears:

   System has either become busy or has become unstable
    - Press any key to return to Windows and wait
    - Press CTRL+ALT+DEL again to restart your computer (all unsaved 
      information will be lost)

When you get this message, you can return to Windows and wait for 
the system to recover, but you will probably have to restart the 
system. When you press CTRL+ALT+DEL after a more severe fault 
occurs, the following message appears:

   This Windows application has stopped responding to the system
    - Press ESC to cancel and return to Windows
    - Press ENTER to close this application (all unsaved information 
      will be lost)
    - Press CTRL+ALT+DEL again to restart your computer (all unsaved 
      information will be lost)

When you get this error message, you can usually press the ESC key 
to return to your application and save your work (if possible) or 
press the ENTER key to close the application and return to Windows; 
this is known as a local reboot. Once you have saved your work or 
returned to Windows, quit Windows and restart your computer to 
prevent additional GP faults.

PREPARING TO TROUBLESHOOT GP FAULTS
===================================

The procedures in the following section provide a proven way to 
troubleshoot GP faults. Many of these troubleshooting steps 
require changes to system configuration files. These changes are 
not intended to be permanent; they should be used as techniques 
for isolating the conflict that caused the GP fault. Before you 
begin making changes, you should back up your system files and 
make a startup (also known as system or boot) disk. This gives you 
the ability to restart your computer and edit your CONFIG.SYS or 
AUTOEXEC.BAT files should any changes cause the system to hang. 
This also ensures that you can return to your original system 
configuration by restoring your original system files after you 
have determined the source of the problem.

To create a startup disk with the necessary files:

1. Insert a formatted disk in your floppy disk drive, type the 
   following command, and press ENTER:

      sys c: a:

   If you are using a version of MS-DOS earlier than 5.0, you also 
   need to copy the COMMAND.COM file to drive A by typing the 
   following command and pressing ENTER:

      copy c:\command.com a:

2. Copy an ASCII text editor (such as MS-DOS Editor [including 
   QBASIC.EXE] or Edlin) to the disk in drive A by typing the 
   following commands, pressing ENTER after each:

      copy c:\dos\edit.com a:
      copy c:\dos\qbasic.exe a:

   If you are running version 4.0 or earlier of Microsoft MS-DOS, 
   your editor is called Edlin. To copy Edlin to drive A, type the 
   following command and press ENTER:

      copy c:\dos\edlin.com a:

3. Copy your AUTOEXEC.BAT, CONFIG.SYS, SYSTEM.INI, and WIN.INI 
   files to the disk in drive A with the following commands:

      copy c:\autoexec.bat a:
      copy c:\config.sys a:
      copy c:\windows\system.ini a:
      copy c:\windows\win.ini a:

   NOTE: If your Windows directory is on a drive other than C, 
   substitute the appropriate drive letter for "c" in the above 
   steps.

SYSTEMATICALLY ISOLATING GP FAULTS
==================================

It is important that you follow the steps in this section in 
sequence. GP faults are usually caused by the interaction of two 
or more applications; therefore, skipping steps may prolong the 
time required to isolate the problem.

NOTE: Most people find the cause of the GP fault in the first half 
of these procedures.

Eliminate the Basics
--------------------

1. Ensure the application was not designed for an earlier version 
   (2.x) of Windows.

   If you are running Windows in standard or 386 enhanced mode, check 
   to see if you are running an application that was designed for an 
   earlier version (2.x) of Windows. Applications designed for 
   Windows 2.x cause errors when run under Windows 3.0 or 3.1 in 
   standard or 386 enhanced mode. Windows displays a warning message 
   when you run an application designed for Windows version 2.0, 
   2.03, 2.1, or 2.11. Such applications should be run only under 
   Windows 3.0 in real mode, as the dialog box suggests. Since real 
   mode is not available in Windows 3.1 or Windows for Workgroups, 
   contact the manufacturer of the application for possible 
   workarounds or to obtain a software upgrade.

2. Run the MS-DOS CHKDSK command with the /F switch.

   NOTE: Before you run this command, you must quit Windows.

   By running CHKDSK /F, any lost allocation units or other file 
   allocation table (FAT) errors are corrected. For more information 
   on CHKDSK, refer to your MS-DOS documentation.

   NOTE: If you are using MS-DOS 6.2 or later, run SCANDISK instead 
   of CHKDSK /F.

3. Ensure system resources are above 60 percent.

   From the Help menu in Program Manager, choose About Program 
   Manager. You should be running Windows in the highest mode your 
   hardware supports, and your system resources should be close to 60 
   percent. If system resources are lower than 60 percent, you may 
   have an application running in the background using resources. If 
   this is the case, close all applications before proceeding.

4. Check the MS-DOS version you are running.

   Your machine should have the proper MS-DOS version for its 
   hardware type. Original equipment manufacturer (OEM) versions of 
   MS-DOS (such as COMPAQ(R) MS-DOS or IBM(R) PC-DOS) should be used 
   only on their respective OEM hardware platforms (that is, COMPAQ 
   MS-DOS on COMPAQ machines only and IBM PC-DOS on IBM machines 
   only).

   NOTE: Microsoft MS-DOS 5 Upgrade and Microsoft MS-DOS 6 Upgrade 
   are platform independent-they function correctly on all 100-
   percent IBM PC/AT(R)-compatible machines.

5. Determine if the problem occurs in standard mode.

   If you are having problems with GP faults in 386 enhanced mode, 
   try running Windows in standard mode (WIN /S) to see if the GP 
   faults still occur. If the errors are present in both standard and 
   386 enhanced mode, the problem may be caused by a conflict between 
   Windows and a hardware device, or you may have a corrupted file.

   NOTE: Standard mode is not available in Windows for Workgroups 
   3.11. Start Windows for Workgroups 3.11 by typing WIN /D:T to 
   prevent loading any 386 enhanced mode virtual device drivers.

6. Run Windows without using the WIN.INI file.

   To determine if you are having problems with corrupted fonts, a 
   corrupted printer driver, or software loading from the run= or 
   load= line, rename the WIN.INI file with the following command, 
   then restart Windows:

      ren c:\windows\win.ini winini.old

   If this procedure corrects the problem, ensure the load= and the 
   run= lines in the [windows] section of the WIN.INI file are either 
   blank or preceded with a semicolon (;) to prevent any software 
   from loading. If this fails to correct the problem, contact 
   Microsoft Product Support Services for assistance in isolating the 
   problem within the WIN.INI file. 

   If the previous procedure does not correct the problem, rename 
   WININI.OLD to WIN.INI, by typing the following command:

      copy c:\windows\winini.old win.ini

7. Reinstall the software that is causing the GP fault.

   If the GP fault can be tracked to a specific application, 
   reinstall the software causing the GP fault. The files on disk may 
   have been corrupted or damaged, or the application may have been 
   improperly installed. Contact the software vendor for assistance 
   if you need help reinstalling the application.

Eliminate Other Software Conflicts Within Windows
-------------------------------------------------

It is essential to determine whether the GP fault is caused by a 
conflict between Windows and your hardware or a conflict between 
Windows and other software. To do this, eliminate possible 
software conflicts before testing your hardware. After you remove 
the software listed below, restart your computer and try to 
reproduce the GP fault.

To eliminate possible software conflicts:

1. Ensure that the StartUp group is empty.

2. Ensure that no screen savers, including built-in Windows screen 
   savers, are running. In the Control Panel window, choose the 
   Desktop icon and ensure the Screen Saver Name list box is empty.

3. Ensure Windows is not being run from a menu program, such as MS-
   DOS Shell.

Configure Windows for the Lowest Level Configuration
----------------------------------------------------

Use the Windows Setup program to configure Windows for the minimum 
necessary hardware devices. Run the MS-DOS version of Windows 
Setup (from the Windows directory [usually named WINDOWS], type 
setup) and select the lowest level configuration of device 
drivers. When you troubleshoot GP faults, use only the standard 
Windows device drivers listed below, if possible.

   Display: VGA (Version 3.0)
   Mouse: No mouse or other pointing device
   Network: No network installed (This is not an option for Windows 
   for Workgroups.)

   NOTE: Systems with EGA cards and/or monitors should use the EGA 
   display driver.

Check for Unsupported Third-Party Drivers
-----------------------------------------

1. The installation programs of some applications modify the 
   SYSTEM.INI and WIN.INI files to enhance the overall functionality 
   of Windows or provide additional features to the Windows 
   environment. For example, programs such as Adobe Type Manager(R) 
   (ATM[R]), Bitstream(R), and SuperPrint add device drivers to the 
   SYSTEM.INI file. Temporarily comment out all lines relating to 
   third-party drivers to ensure that Windows uses a minimum 
   configuration for testing purposes. (To comment out a line, use an 
   ASCII text editor, such as Windows Notepad, to edit the .INI file 
   and place a semicolon at the beginning of the appropriate line.)

   If this corrects the problem, the problem was most likely caused 
   by one of the drivers you commented out. To identify which line is 
   causing the problem, replace the commented-out lines one by one 
   until the problem reoccurs.

2. The statements below are those most commonly altered by third-
   party software manufacturers. Make sure your configuration does 
   not differ from the default Windows configuration shown below:

      SYSTEM.INI                 | WIN.INI
   ---------------------------------------------
      [boot]                     | [windows]
      shell=progman.exe          | load=
      system.drv=system.drv      | run=
      keyboard.drv=keyboard.drv  |
      mouse.drv=mouse.drv        |
      display.drv=vga.drv        |
      comm.drv=comm.drv          |
      sound.drv=mmsound.drv      |

Eliminate Software Conflicts at the MS-DOS Level
------------------------------------------------

Check for incompatible terminate-and-stay-resident (TSR) programs 
or unsupported device drivers in your CONFIG.SYS and AUTOEXEC.BAT 
files.

Temporarily comment out all lines relating to device drivers and 
TSR programs that are not required to start your system. These may 
include virus-detection programs, disk-imaging programs, undelete 
utilities, caching programs, CD-ROM drivers, multimedia drivers, 
terminal-emulation software, and so on. (To comment out a line, 
use a text editor, such as MS-DOS Editor or Edlin, open the 
AUTOEXEC.BAT or CONFIG.SYS file, and type "rem" (without the quotation
marks) at the beginning of the line, then save the file and restart 
your computer.)

NOTE: Do not comment out network files if the Windows files are on 
a network server. 

Minimum MS-DOS configuration for Windows versions 3.0 and 3.1:

   CONFIG.SYS                       | AUTOEXEC.BAT
-----------------------------------------------------------------
   files=50                         | path c:\;c:\dos;c:\windows
   buffers=30                       | prompt $p$g
   device=c:\\himem.sys       | set temp=c:\
   stacks=9,256 (Windows 3.1 only)  |

Minimum MS-DOS configuration for Windows for Workgroups 3.1 (with 
the Microsoft Windows network):

   CONFIG.SYS                         | AUTOEXEC.BAT
-----------------------------------------------------------------------
   files=50                           | c:\\net start
   buffers=30                         | path c:\;c:\dos;c:\windows
   device=c:\\himem.sys         | prompt $p$g
   stacks=9,256                       | set temp=c:\
  *device=c:\\protman.dos       |              
      /I:\protocol.ini          |
   device=c:\\.dos  |
   device=c:\ \workgrp.sys      |

*NOTE: This should appear on a single line in your CONFIG.SYS file.

Minimum MS-DOS configuration for Windows for Workgroups 3.11 (with 
the Microsoft Windows network):

   CONFIG.SYS                   | AUTOEXEC.BAT
--------------------------------------------------------------
   files=50                     | c:\\net start
   buffers=30                   | path c:\;c:\dos;c:\windows
   device=c:\\himem.sys   | prompt $p$g
   tacks=9,256                  | set temp=c:\
   device=c:\\ifshlp.sys  |

CAUTION: Before modifying these files, make sure you don't comment 
out lines pertaining to other hardware-specific device drivers, 
such as disk-compression utilities, extended memory boards, third-
party disk-partitioning programs, and so on. If you do not know 
the purpose of a line in your CONFIG.SYS or AUTOEXEC.BAT file, do 
not comment it out. The following drivers may be required to start 
the computer or to access your hard disk:

   Device driver   | Function
----------------------------------------------------------------
   SSWAP.COM       | Stacker(TM) disk compression
   STACKER.COM     | Stacker disk compression
   DASDDRVR.SYS    | IBM BIOS fix
   DMDRVR.SYS      | Ontrack disk partition
   SSTORE.SYS      | SpeedStor(R) disk compression
   ASPI4DOS.SYS    | Adaptec(TM) SCSI BIOS extensions
   SCSIHA.SYS      | Adaptec SCSI buffering device

If the previous procedure corrects the problem, the problem is 
related to one of the drivers or TSR programs that you commented 
out. To identify which line is loading the TSR program or device 
driver that causes the error, restore the commented-out lines one 
by one until the problem reoccurs.

Eliminate Potential Network Conflicts
-------------------------------------

If the machine is running on a network, disabling the network 
software is the easiest and quickest way to determine whether the 
network software is causing the problem.

To disable the network software:

1. If Windows is running on the local hard disk drive (that is, you 
   are not running a network installation of Windows [installed by 
   running SETUP /N]), comment out all network drivers and statements 
   from the AUTOEXEC.BAT and CONFIG.SYS files.


2. Configure Windows for "No network" by changing to the WINDOWS 
   directory (CD \WINDOWS), typing "setup" (without the quotation 
   marks), and changing the installed network to "No network installed."

   NOTE: "No network installed" is not a choice in Windows for 
   Workgroups. For Windows for Workgroups 3.1, comment out the 
   network statements in the CONFIG.SYS and AUTOEXEC.BAT files. When 
   you restart your system, ignore the error messages about the 
   network. For Windows for Workgroups 3.11, type "win /n" (without 
   the quotation marks) to disable network functionality.

3. Ensure login scripts are not altering the PATH environment 
   variable.

   Check the PATH environment variable prior to starting Windows. To 
   do this, type "set" (without the quotation marks) to display the 
   path. Replace the current path command with the minimum path required 
   to test for GP faults. For example

      path=c:\windows;c:\dos

   or, if Windows is running over the network

      path=:\windows;:\;c:\dos;:\

   where "c:" is your hard disk drive, "d:"is a network drive, 
    is the directory containing the shared Windows 
   program files, and  is the directory containing the 
   network files.

   NOTE: If you need to test a specific application, include the 
   application's directory in the path.

4. Make sure that your WINDOWS directory does not contain any .DRV 
   files. These files should be located either in the WINDOWS\SYSTEM 
   subdirectory or in the shared directory on the server if you are 
   running a network installation of Windows.

   NOTE: If you are running a network installation of Windows, you 
   should not have a WINDOWS\SYSTEM directory on your local hard disk 
   drive or in the shared Windows directory on the network server.

5. Make sure you are using the correct version of the network 
   shell. (Use the version that ships with Windows.)

Eliminate Potential Video Conflicts
-----------------------------------

If a poorly designed or corrupted video driver is installed, GP 
faults may occur at seemingly random times, sometimes very 
frequently. You may also see a blank screen or the system may hang 
when you quit an MS-DOS-based application that is running in a 
window. These problems can be caused by a poorly designed or 
corrupted video driver or by the use of the incorrect video 
grabber file. Use the following steps to ensure you are using a 
compatible video driver:

1. Quit Windows and use the Microsoft Diagnostics (MSD) program to 
   check the video hardware. If you have a video BIOS dated earlier 
   than 1988, contact your video card manufacturer to see if a more 
   recent version of the BIOS is required for use with Windows. If a 
   high-resolution card, such as the ATI or Orchid coprocessor card, 
   is installed, make sure that it is configured correctly for your 
   hardware--these cards may require that you select a vertical scan 
   rate and monitor type.

2. Install the generic VGA driver by quitting Windows and running 
   Setup from the WINDOWS directory. If this driver is already 
   installed, press the ESC key when you are prompted with the 
   following message:

      To replace the currently installed driver, press ESC.

   This ensures that new video driver, font, and video grabber files 
   are installed. If this fails to correct the problem, repeat this 
   procedure and install the VGA 3.0 driver. If the problems persist, 
   install the EGA video driver. If none of these drivers improves 
   the situation, reinstall the standard VGA video driver and 
   continue troubleshooting.

   NOTE: The VGA (version 3.0) driver is not available in Windows 
   3.0. EGA is not available in Windows for Workgroups 3.11.

3. Make sure that the correct 286 and 386 grabber files are 
   installed. The following entries should be present in the [boot] 
   section of the SYSTEM.INI file; the corresponding files should be 
   in the WINDOWS\SYSTEM subdirectory:

   In Windows 3.0:

      286grabber=vgacolor.gr2
      386grabber=vga.gr3

   In Windows 3.1 and Windows for Workgroups 3.1:

      286grabber=vgacolor.2gr
      386grabber=vgadib.3gr or 386grabber=vga.3gr

   In Windows for Workgroups 3.11:

      386grabber=vga.3gr

Ensure You Are Using the Correct Switch for HIMEM.SYS
-----------------------------------------------------

HIMEM.SYS is the default device driver Windows uses in the 
standard and 386 enhanced modes to access extended memory, 
including the high memory area (HMA)--the first 64K of extended 
memory (1024K-1088K). HIMEM.SYS accesses the HMA through the A20 
line of memory using A20 "handlers." The method used to access the 
HMA depends on the hardware you are using, so HIMEM.SYS has been 
designed to use several different A20 handlers.

HIMEM.SYS follows a routine at load time to determine which A20 
handler is appropriate for your machine. Unfortunately, some 
nonstandard machines do not respond to the HIMEM.SYS tests, which 
can result in the wrong A20 handler being selected. Using the 
incorrect A20 handler can result in many problems, such as slow 
system performance and GP faults. The system may also hang when 
HIMEM.SYS loads, leaving the following message on the screen:

   HIMEM: DOS XMS Driver, Version x.xx - MM/DD/YY

The /MACHINE switch is used to gain control of the A20 line by 
forcing HIMEM.SYS to use a specific handler. For example:

   device=c:\\himem.sys /machine:1

   -or-

   device=c:\\himem.sys /m:1

To test the different HIMEM.SYS switches on your machine, edit the 
CONFIG.SYS file with an ASCII text editor and add the /MACHINE 
switch with one of the machine-specific handler numbers (1-16). If 
you do not know which number to use, refer to your current MS-DOS 
or Windows documentation. For most IBM PC/AT 100 percent-
compatible machines, one of the IBM PC/AT compatible A20 handler 
switches (/M:1, /M:11, /M:12, /M:13) should work. If your computer 
is not listed in the documentation, you are not sure which number 
to use, or the machine number for your computer doesn't correct 
the problem, try these machine numbers in the following order: 1, 
11, 12, 13, 8, 2-7, 9-10, 14-16. Check your current MS-DOS or 
Windows documentation for the list of machines that require a 
specific A20 handler.

WARNING: When you are testing to see which A20 handler is 
appropriate, make sure you have a startup MS-DOS disk with an 
ASCII text editor (such as MS-DOS Editor or Edlin), because some 
A20 handlers will cause your machine to hang.

For MS-DOS versions 6.2 and later, you can force the testing of 
XMS memory with the TESTMEM:ON parameter. If you continue to have 
problems accessing extended memory, try enabling and disabling XMS 
testing. For example:

   device=c:\\himem.sys /testmem:on

   -or-

   device=c:\\himem.sys /testmem:off


Ensure Windows Is Configured for the Correct Computer Type and Network
----------------------------------------------------------------------

Some machines and networks require that you override the Windows 
Setup default setting for the computer type and network. If the 
correct selection is not made during Setup, Windows may not 
operate correctly, or you may receive GP faults.

Machines that must be specifically selected during Windows Setup 
include the following:

                                              Windows      | Workgroups
Machine                                     3.0 | 3.1/3.11 | 3.1 | 3.11
------------------------------------------------------------------------
AST(R)--all 80386- and 80486-based machines  X  |    X     |     |
AST Premium 386/25 and 386/33 (CUPID)           |          |  X  |  X
AT&T(R) PC                                      |    X     |  X  |  X
AT&T NSX 20--Safari Notebook                    |    X     |  X  |  X
Everex(TM) Step 386/25 (or compatible)       X  |    X     |  X  |  X
Hewlett-Packard(R)--all machines             X  |    X     |  X  |  X
IBM PS/2(R) Model 70P                           |    X     |  X  |  X
IBM PS/2 Model L40sx                            |    X     |  X  |  X
Intel(R) 386SL-based system with APM            |    X     |  X  |  X
MS-DOS system with APM                          |    X     |  X  |  X
NCR-all 80386- and 80486-based machines         |    X     |  X  |  X
NCR PC386sx                                  X  |    X     |     |
NCR PC 925                                   X  |          |     |
NEC(R) PowerMate SX Plus                     X  |    X     |  X  |  X
NEC ProSpeed 386                             X  |    X     |  X  |  X
Toshiba(R) 1200XE                               |    X     |  X  |   
Toshiba 1600                                 X  |    X     |  X  |  X
Toshiba 5200                                 X  |    X     |  X  |  X
Zenith(R)-all 80386-based machines           X  |    X     |     |
Zenith Data Systems-all 80386-based machines    |    X     |     |
Zenith-all 386/486-based machines               |          |     |  X

Networks that must be specifically selected during Windows Setup 
include the following:

NOTE: This information does not apply to Windows for Workgroups.

                                                     Windows
Network                                             3.0 | 3.1/3.11
---------------------------------------------------------------------
3Com(R) 3+Open(R) LAN Manager (XNS only)             X  |
3Com 3+Open                                             |    X
3Com 3+Share(R)                                      X  |    X
Artisoft(R) LANtastic(R)                                |    X
Banyan(R) VINES(R) 4.0                               X  |    X
DEC(R) Pathworks(TM)                                    |    X
IBM OS/2(R) Lan Server                                  |    X
IBM PC LAN Program                                   X  |    X
LAN Manager versions 1.x (or 100-percent compatible) X  |    X
LAN Manager 2.0 (or 100-percent compatible)          X  |    X
LAN Manager 2.1 (or 100-percent compatible)             |    X
Novell(R) NetWare(R)                                    |    X
TCS(R) 10NET                                            |    X

If your computer and/or network is on either of these lists and 
you did not select your computer type or network specifically 
during Setup, quit Windows and run the MS-DOS version of Setup 
from the WINDOWS directory. This allows you to make the proper 
selection without having to reinstall Windows.

Use 386 Enhanced Mode for Troubleshooting
-----------------------------------------

If GP faults occur in 386 enhanced mode but do not occur in 
standard mode, your system may have a memory conflict in the upper 
memory blocks (UMBs). Such errors occur only in 386 enhanced mode 
and most frequently in Windows 3.0, because version 3.0 does not 
inherit UMB usage from the expanded memory manager (EMM).

To eliminate the possibility of a UMB conflict:

1. Edit the SYSTEM.INI file with the MS-DOS Editor or Edlin and 
   insert the following line in the [386Enh] section:

      EMMExclude=A000-EFFF

      NOTE: This line is not case sensitive.

   If you are using an expanded memory manager, such as EMM386.EXE or 
   Qemm(TM), with Windows 3.1 and Windows for Workgroups, you must 
   either disable it or exclude the memory range shown above with the 
   appropriate EMM. This information is inherited by Windows from the 
   EMM and overrides any entries in the SYSTEM.INI file. The 
   following is an example of excluding the memory range with 
   EMM386.EXE:

      device=c:\windows\emm386.exe noems x=A000-EFFF

   IMPORTANT: If you are using Windows 3.1 or Windows for Workgroups, 
   and you are not using an EMM, use the command WIN /D:X to load 
   Windows from the MS-DOS command prompt. The /D:X switch excludes 
   the memory range A000-EFFF from mapping, similar to the statement 
   EMMExclude=A000-EFFF in the [386Enh] section of the SYSTEM.INI 
   file. However, as with the EMMExclude= statement, this switch is 
   overridden by any settings inherited from the EMM.

2. If making the above change corrects the problem, determine the 
   position of all hardware adapters in the adapter segment and 
   exclude them specifically, rather than excluding the entire 
   region. If necessary, you can use multiple EMMExclude= lines to do 
   this. If you leave the entire range excluded, Windows cannot set 
   up expanded memory for MS-DOS-based applications.

   If you are using a Micro Channel(R) Architecture (MCA) bus machine, 
   such as an IBM PS/2, you can determine the adapter location by 
   restarting the machine with the IBM Reference Disk in drive A. If 
   you are using an Industry Standard Architecture (ISA) bus machine, 
   consult your adapter documentation and/or your manufacturer's 
   technical support service for information on the memory locations 
   the bus machine uses. 

3. Disable virtual hard disk access.

   If you are running Windows 3.1 or Windows for Workgroups, start 
   Windows with the /D:V parameter (WIN /D:V). If this prevents the 
   GP faults, add the following line in the [386Enh] section of the 
   SYSTEM.INI file: 

      VirtualHDIRQ=OFF

   If you are running Windows 3.0, edit the SYSTEM.INI file and 
   comment out the VirtualHDIRQ= line in the [386Enh] section. (To 
   comment out a line, use an ASCII text editor, such as Windows 
   Notepad, to edit the .INI file and place a semicolon at the 
   beginning of the appropriate line.)

4. Ensure your permanent swap file is not corrupted.

   If you are running Windows 3.1 or Windows for Workgroups, you can 
   remove your permanent swap file by using the 386 Enhanced icon in 
   the Control Panel window.

   If you are running Windows 3.0, restart Windows in real mode and 
   run the Swapfile program with the following steps:

   a. Start Windows in real mode by typing "win /r" (without the 
      quotation marks).

   b. Close any applications that load automatically.

   c. From the File menu, choose Run.

   d. Type "swapfile" (without the quotation marks) and then press 
      the ENTER key.

   If removing the permanent swap file corrects the problem, optimize 
   your hard disk with a program such as Symantec's Speed Disk or PC 
   Tools(TM) Compress and then reinstall the permanent swap file.

5. Turn off 32-bit disk access and 32-bit file access.

   If you are running Windows 3.1 or Windows for Workgroups, start 
   Windows with the /D:F parameter (WIN /D:F) to disable 32-bit disk 
   access.

   If you are running Windows for Workgroups 3.11, start Windows with 
   the /D:C parameter (WIN /D:C) to disable 32-bit file access. The 
   /D:F and the /D:C parameters (WIN /D:FC) can be combined to 
   disable 32-bit disk access and 32-bit file access at the same 
   time.

REINSTALLING WINDOWS
====================

If you have followed all the above steps and still receive GP 
faults, there is most likely a problem with the machine or the way 
the hardware is configured. Use the following procedure to 
reinstall Windows to eliminate any possible remaining software or 
disk-integrity conflicts:

1. Remove any hardware such as external drives, modems, sound 
   cards, and so forth from the machine. If the machine uses other 
   special hardware, such as a full-page monitor, printer-sharing 
   devices, or hardware keys used for copy protection, these items 
   should be removed or swapped for standard devices that are known 
   to work correctly.
   
2. Use the machine's CMOS Setup program to disable any feature that 
   moves memory. (Consult your hardware documentation for specific 
   instructions on modifying the CMOS settings.) This includes video 
   shadowing, ROM BIOS shadowing, and any feature dealing with A20 
   handling. Also make sure the machine's primary startup (boot) 
   drive is drive A.

3. Delete any reference to Windows on the PATH command in your 
   AUTOEXEC.BAT file. Also, remove the DEVICE command for HIMEM.SYS 
   from the CONFIG.SYS file. For more information, see the "Eliminate 
   Software Conflicts at the MS-DOS Level" section on page 6 of this 
   document.

4. Run Windows Setup with the following steps:

   a. To run Windows Setup in Custom mode, type "a:setup" (without the
      quotation marks) and press ENTER. When prompted for Express or 
      Custom Setup, press C for Custom Setup.

   b. When you are prompted with the current Windows directory name, 
      choose a new directory (such as WINTEST) to make sure the files 
      are copied to a new location on your hard disk.

   c. At the configuration screen, ensure the appropriate options 
      are selected for your specific hardware. Make sure the Computer 
      setting is correct, set the Mouse option to "no mouse or pointing 
      device," and set the Display option to VGA. Press the ENTER key to 
      continue.

   d. In the Windows Setup dialog box, clear the Set Up Printers 
      check box (press ALT+P) and the Set Up Applications Already On Hard 
      Disk(s) check box (press ALT+A), then choose the Continue button.

   e. Clear all five check boxes in the Component section of the 
      Windows Setup dialog box and choose the Continue button. Since you 
      don't have mouse functionality at this time, clear the check boxes 
      as you did in the previous step by pressing the ALT key plus the 
      underlined letter in the component name.

   f. Choose the Change button in the Virtual Memory dialog box and 
      then choose the OK button.

   g. Under New Settings, select None in the Type box.
  
   h. Choose the Change button and then choose the Yes button.

   i. Choose the Continue button to allow Windows Setup to update 
      your CONFIG.SYS and AUTOEXEC.BAT files.

You now have the minimum Windows installation, with the new Windows files 
in a different location on the hard disk. If this doesn't eliminate the 
GP faults, a hardware or BIOS conflict exists somewhere in your system.

Last Update
8/11/98

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