DOCUMENT:Q82763  11-OCT-1999  [win95x]
TITLE   :PS/2 Appears to Hang When Exiting Windows 3.1
PRODUCT :Microsoft Windows 95.x Retail Product
PROD/VER:WINDOWS:3.1,3.11
OPER/SYS:
KEYWORDS:win31

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The information in this article applies to:

 - Microsoft Windows versions 3.1, 3.11 
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SYMPTOMS
========

Some IBM PS/2 models may appear to stop responding (hang) when you exit Windows
version 3.1. The computer eventually restarts; however, it remains frozen for up
to a minute while the mouse port is reinitialized.

This problem is most severe on PS/2 models 56 and 57. It also occurs on models
50z, 55sx, 70, 80, 90, and 95.

CAUSE
=====

This behavior is caused by a problem in the IBM PS/2 mouse BIOS.

WORKAROUND
==========

The problem can be corrected by adding the following line to the [386Enh]
section of SYSTEM.INI:

   InitPS2MouseAtExit=FALSE

This prevents Windows from attempting to reinitialize the PS/2-style mouse port
prior to exiting to MS-DOS. This may cause problems when you run some
mouse-aware, MS-DOS-based applications after exiting Windows.


PS/2 products included here are manufactured by a vendor independent of
Microsoft; we make no warranty, implied or otherwise, regarding these products'
performance or reliability.

Additional query words: 3.10 3.11 InitPS2MouseAtExit ps2 hangs init slow Initps2mouseportatexit

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Keywords          : win31 
Technology        : kbWin3xSearch kbZNotKeyword3 kbWin310 kbWin311
Version           : WINDOWS:3.1,3.11

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