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The Power Switch


To function properly, all computer and network components must be turned on and powered up. As obvious as this is, network administrators often hear a user complain, “My computer is on, but my monitor is dark.” In this case, our response is to ask, “Is the monitor turned on?” After a pause, the voice on the other end usually says sheepishly, “Oh. Thanks.”


Most systems include a power indicator such as a Power or PWR light, and the power switch typically has a 1 or an On indicator. However, the unit could be powerless even if the power switch is in the On position. Thus, you need to check that all power cables are plugged in, including the power strip.


Remember that every cable has two ends, and both must be plugged in to something.


When troubleshooting power problems, start with the most obvious device and work your way back to the power service panel. There could be any number of power problems between the device and the service panel, including a bad power cable, bad outlet, bad electrical wire, tripped circuit breaker, or blown fuse. Any of these items can cause power problems at the device.

Operator Error


The problem may be that the user simply doesn’t know how to perform the operation correctly; in other words, the problem may be due to OE (operator error). Those in the computer and networking industry have devised several colorful expressions to describe operator error:


■    EEOC (Equipment Exceeds Operator Capability)


■    PEBCAK (Problem Exists Between Chair And Keyboard)

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