If the PC is turned off it shouldn't turn itself back on. That takes a power switch.
Wake up? Evidently you are using hybernate/sleep/stand-by, not the Start, Turn off the Computer, Turn off. Below is how to disable the Wake on Lan:
Click Start, right-click My Computer, and select Properties.
A System Properties window appears.
Click the Hardware tab, and then the Device Manager button.
Under Network adapters, double-click the name of the device used on the network.
Click the Power Management tab.
Deselect the Allow this device to bring the computer out of standby option under Power Management.
Power management will remove power from the NIC, not the modem. If the PC is turned OFF, not hybernate/sleep/stand-by, then you're safe. But I leave my cable modem on, my router on, and turn my PC OFF.
I recently got Cable internet service. Since then, my computer turns itself on at night. Last night I unplugged the power cable to the modem, and the computer stayed off. I have since disabled both of the Remote access settings in Services. These were previously set to Manual. I could not locate a ?Wake on Lan? listing in my BIOS.
I?ve noticed that in Local Area Connection / Properties / Configure / Advanced / the ?WakeUp on ARP/PING? is enabled. Could this be causing my computer to power-up on it?s own?
Also - in Power Management, I have the box checked which reads ?Allow the computer to turn off this device to save power?, but the modem remains lit-up after shutdown. Does that mean that the modem is still on, and therefore leaving my system vulnerable to outside access? Is there a setting to power off the modem, when the computer is powered off?
Win XP/SP2

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