WARNING!!!!
Any changes you make in the registry could make the computer unstable or UN-operable.
To do this click Start and in the Start Search type in regedit. Once again I should warn you to be careful when working on your registry, as incorrectly editing it can result in your computer not working properly. Make sure you back up your registry before making any changes, and if you are not completely comfortable with changing your registry, it?s best to leave it alone, or ask someone who is comfortable editing registries to help you.
In the registry editor, browse down to HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control.
On the right-hand side of the screen you should see a key called WaitToKillServiceTimeout with the value of 20000. This tells Windows Vista to wait 20000 milliseconds (20 seconds) for the service to stop after notifying the service that the system is shutting down. You can change this setting to 5000 (5 seconds), however you shouldn?t go any lower as you need to give the services time to shut down properly.
Please post back if you have any more problems or questions.
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