Here's the documentation from Microsoft TechNet:

PSS ID Number: Q188107
Article last modified on 06-16-1999

WINDOWS:95

WINDOWS


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

 - Microsoft Windows 98
 - Microsoft Windows 95
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SYMPTOMS
========

When you attempt to upgrade Microsoft Windows 3.1 to Windows 95/98, you may
receive the following error message:

   SUWIN
   An error has occurred in your application. If you choose ignore you
should
   save your work in a new file. If you choose close, your application will
   terminate."

When you click Close, you may receive the following error message:

   Application Error
   SUWIN caused a general protection fault in module setupx.dll @ 0012:1346

CAUSE
=====

This behavior can occur if you disable virtual memory in Windows 3.1 before
you
run Windows 95/98 Setup.

RESOLUTION
==========

To resolve this issue, enable virtual memory in Windows 3.1 before running
Windows 95/98 Setup, or quit Windows to MS-DOS, and then run Setup from
MS-DOS.
To enable virtual memory in Windows 3.1 before running Windows 95/98 Setup,
follow these steps:

1. In the Main group, open Control Panel and double-click 386 Enhanced.

2. Click Virtual Memory, and then click Change.

3. In the Type box, click Permanent or Temporary, and then click OK.

Additional query words: swap file suwin error

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Keywords          : kberrmsg kbsetup win95 win98
Version           : WINDOWS:95
Platform          : WINDOWS
Issue type        : kbprb
 ===========================================================================
=
Copyright Microsoft Corporation 1999.




> -----Original Message-----
> From: PCBUILD - Personal Computer Hardware discussion List
> Sent: Tuesday, September 21, 1999 1:34 PM
> To: [log in to unmask]
> Subject: Re: [PCBUILD] Application Error
>
> ----- Original Message -----
> From: J & M Home Computer Services <[log in to unmask]>
>
> When I'm trying to install Windows 98 I get the following error.
>
> Application Error: SUWIN caused a General Protection fault in module
> Setupx.dll at 0004:5CCE
>
> I've seen this error before but can't remember if it's a hardware or
> software fault.
>
> Can someone put some light on this please?
>
> Thank you,
>
> Michael J. Murray
> [log in to unmask]

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