When Windows XP wont powerdown automatically, the APM/NT Legacy Power Node may not be enabled. To enable this, right-click on the My Computer icon, click Properties | Hardware | Device Manager | View. Check the box labeled Show Hidden Devices. If its available on your computer, there will be a red X on the APM/NT Legacy Node. Try enabling it and see if this resolves the powerdown problem (Tip from Terri Stratton). Or, to check the other side of the APM/ACPI coin, open the Power Options applet in Control Panel. If there is an APM tab, make sure the Enable Advanced Power Management Support box is checked.
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