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Q76582: PRB: Reset A20 Bit Set During DPMI Simulate Interrupt Crash

Article: Q76582
Product(s): Microsoft Windows Software Development Kit
Version(s): WINDOWS:3.0,3.1
Operating System(s): 
Keyword(s): kb16bitonly
Last Modified: 06-NOV-1999

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The information in this article applies to:

- Microsoft Windows Software Development Kit (SDK) versions 3.0, 3.1 
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SYMPTOMS
========

A Windows-based application that specifies "reset interrupt controller and A20
line" when calling the MS-DOS protected mode interrupt (DPMI) function "Simulate
Real Mode Interrupt" can cause Windows to crash.

RESOLUTION
==========

Applications that use the "Simulate Real Mode Interrupt" function must ensure
that this bit is not set.

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

The "Simulate Real Mode Interrupt" function is documented in the DPMI
specification.

Additional query words: 3.00 no32bit 3.10

======================================================================
Keywords          : kb16bitonly 
Technology        : kbAudDeveloper kbWin3xSearch kbSDKSearch kbWinSDKSearch kbWinSDK300 kbWinSDK310
Version           : WINDOWS:3.0,3.1

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