DOCUMENT:Q222584  01-AUG-2001  [win95x]
TITLE   :BUG: Blue Screen Occurs When Disabling a USB Controller
PRODUCT :Microsoft Windows 95.x Retail Product
PROD/VER:WINDOWS:95; Win95:
OPER/SYS:
KEYWORDS:kbDDK kbKMode kbOSWin95OSR210 kbOSWin95OSR250 kbVideo kbOSWin95 kbVideoTech

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The information in this article applies to:

 - Microsoft Windows 95 
 - Microsoft Windows 95 Driver Development Kit (DDK) 
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SYMPTOMS
========

When running on Windows 95 OSR 2.1 or OSR 2.5, a blue screen appears when
manually or programmatically disabling a USB host controller.

CAUSE
=====

This problem occurs because of a fault in the USB host controller driver.

RESOLUTION
==========

There is no workaround for Windows 95 OSR 2.1 or 2.5. The problem does not occur
under Windows 98. A USB controller can be successfully disabled using Device
Manager, or programmatically via DiChangeState.

STATUS
======

Microsoft has confirmed this to be a bug in the Microsoft products listed at the
beginning of this article.

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

If a user tries to disable a USB host controller via Device Manager or via a
DiChangeState call, a blue screen occurs because of a fault in the USB host
controller driver (Uhcd.sys or Openhci.sys).

Additional query words:

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Keywords          : kbDDK kbKMode kbOSWin95OSR210 kbOSWin95OSR250 kbVideo kbOSWin95 kbVideoTech 
Technology        : kbAudDeveloper kbWin95search kbWin95DDKSearch kbWinDDKSearch kbZNotKeyword3 kbWin95DDK
Version           : WINDOWS:95; Win95:
Issue type        : kbbug
Solution Type     : kbnofix

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