How to Wake a Computer From Sleep Mode in Windows Vista

1. Put the computer to sleep. For a laptop, close the computer. For a desktop, press “Start” and click the arrow on the lower right of the Start box, then select “Sleep.” You may also press the “Sleep” button on your keyboard. (If you often hit the “Sleep” button accidentally, you can disable it. In the Control Panel, select 'System and Maintenance,' then 'Power Options.' Click 'Choose what the power buttons do.' Next to “When I press the sleep button,” change the setting to “Do nothing.”)
2. Wake your laptop computer by opening it.
3. Wake the desktop computer with your mouse. Click the mouse button. If your computer does not respond, move the wheel.
4. Wake your computer from the keyboard. Some keys, like “Enter,” may not always wake the computer; press a letter or number key.
5. Troubleshoot sleep mode. If you wake the computer and a device crashes, or you receive an “Stop Error” message, Microsoft recommends obtaining the latest Windows Vista service pack, or looking for a hotfix.If you cannot wake the computer from sleep mode, restart by pressing and holding the power button, then check “Power Options and Sleep Mode Problems” at Windows Vista Forums for problem-solving steps.