Sony VAIO PCG-R505ELK User Manual page 163

My computer stops responding or does not shut down.
It is best to shut down your computer using the Shut Down command on the Windows Start menu. Using other methods,
including those listed below, may result in loss of unsaved data.
 On the Windows taskbar, click Start, click Shut Down, then select Shut Down again, and click OK.

If you cannot shut down your computer as described in the preceding step, press the Ctrl+Alt+Delete keys
simultaneously and click Shut Down on the Windows Security window.

If the preceding step does not work, press and hold the power button for at least four seconds to turn off the
power.
 Unplug the computer from the AC adapter and remove the battery pack from your computer.

If your computer stops responding while playing a CD or DVD, press the Ctrl+Alt+Delete keys simultaneously, and
click Shut Down on the Windows Security window.
Pressing the Ctrl+Alt+Delete keys simultaneously or turning off the computer with the power switch may result in data
loss in files that are currently open.
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