Cannot shut off PC using on/off button

What does it do when you Press the button.
If nothing make sure that the wires are connected.
If it goes into sleep or stand by check the power management settings.

Press and hold the button for five seconds (measured). Your operating system is preventing it from shutting off because the button is bumped.

What O/S are you useing and what kind of computer? If you have or can down load the manual, make sure the switch is plugged into the main board correctly, not backwards. Some bios let you disable fast shut down. Do you have a reset button? And if soif you press it will the computer reboot? Most O/S will let you create a log file of whats happening, try that to see whats holding up the shut down. Try some of the freeware out there that will shut the system down with one click.

Is your PC an ATX, or AT type?

If an AT type, and the power button doesn't turn it off, the switch is bad.

If an ATX, what is the last screen that you get?
If you get the screen that says it is okay to turn off your computer, you need to correct power management settings.

Start in the BIOS settings.
For many motherboards, you need to enable power management to have automatic shutdown, or the power button work.

Next, check if power management is enabled in Windows.
Also, check in device manager for a "?" or "!" next to APM or ACPI. That would indicate that windows has a problem with the driver for powermanagement for your MB.

If the system stops on any other screen, you have a shutdown problem.
Depending on which versionof windows, there are several options.
Check out the shutdown section at
www.aumha.org
Also, check for a shutdown trouble shooter or update from Microsoft.

Check whether your pc is running on the atx or at power supply. If it's running on the latest power supply which is ATX then is using the soft power technology. Please press for five seconds in order to force the pc to shutdown, if not shutdown it from the windows :)

It this is a fairly new PC, it is not uncommon for the power button to have a delay. You can try pressing and holding the power button down for 5-15 seconds or so. This is suposed to eliminate accidental shut downs by accidently bumping or hittingthe power button, but it's kind of a pain.... I hope this helps.

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