KB950749 Update causes Win XP Pro to Hang on Reboot at MUP.SYS

KB950749 Update causes Win XP Pro to Hang on Reboot at MUP.SYS. Had to
disable onboard USB controller in BIOS to restart Windows XP Pro.

Unistalled KB950749 Update and then enabled onboard USB controller in BIOS.
Windows started without a hitch.

What is the problem?

Please advise

 

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