Updating EHCI USB 2.0 driver may cause USB 1.1 devices to stop functioning (813139)
The information in this article applies to:
- Microsoft Windows XP Professional SP1
SYMPTOMSIf you try to update the device driver for an EHCI USB 2.0
host controller by using the Update Driver function in
Device Manager, USB 1.1 devices that are attached to the
controller may stop functioning.CAUSETo support USB 1.1 devices, a USB 2.0 host controller has
one or more USB 1.1 compatible controllers that are enumerated as separate PCI
functions by the operating system. The USB driver stack on Windows XP Service
Pack 1 synchronizes the operation of a USB 2.0 host controller with the
operation of its USB 1.1 compatible controllers. When the device driver for the
USB 2.0 controller is updated by using the Device Manager, the controller is
programmatically removed by the operating system before the driver is
updated.
Due to the synchronization of the USB 2.0 controller and its
USB 1.1 compatible controllers, the USB driver stack also removes the USB 1.1
compatible controllers when the USB 2.0 controller is removed. When the device
driver update is complete, the USB 2.0 controller is restarted; however the
USB 1.1 compatible controller remains disabled. Therefore, any USB 1.1
devices that are attached to the controller no longer function.RESOLUTIONTo restart the USB 1.1 compatible controllers after you
update a USB 2.0 controller, you have to re-enumerate the hardware tree. To
re-enumerate the hardware tree, use one of the following methods. - In Device Manager, on the Action menu,
click Scan For Hardware Changes.
- Restart the computer.
Note We do not recommend that you update the USB 2.0 host controller driver
by using the Device Manager if you are using a USB keyboard and a mouse input device. When you update the USB 2.0 host controller driver
by using the Device Manager, the keyboard and the mouse do not
function, and you cannot control the system or safely restart the
computer. STATUSMicrosoft has confirmed that this is a problem in the Microsoft products that are listed in the "Applies to" section.
| Modification Type: | Major | Last Reviewed: | 9/7/2005 |
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| Keywords: | kbUSB kbprb KB813139 kbAudDeveloper kbAudITPRO kbAudOEM kbAudEndUser |
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