I have experienced an odd occurence my computer which i shut down has truned itself back on during the night. Coincidently my bullguard anti virus and firewall have gone pear shaped. Has anyone else experienced similar problems?
Modem wake on ring is more likely to be the problem , press F1 or F2 or delete as the PC is booting ( detecting hard drive / CD / DVD etc. depends on which bios you have , you should find it in Power settings .
Switch computer power off at the mains - that will put a stop to it. I always do this in any case - a single switch to turn off the router (my wife frequently needs this when my PC is turned off) and another for everything else.