My XP Home PC strangely boots up at 12.00a.m. everyday. I disabled the scheduled tasks at "services.msc" and"msconfig/services". Yet, it persists everyday at the stroke of midnight without fail. I don't know if this has anything to do with the boot-up but I recently fixed an NTLDR error using the
Windows Recovery Console on the Installation CD. To do this , I had changed the first boot order in the BIOS from hard drive to CD-ROM and it remains such till to date. Help.

its a bios setting

check for a auto startup function in bios
its ether called
auto start
auto boot
or
schedules startup

No, no way.
You must have an infection.
Maybe Boni or Patio will move this to the virus forum.

except how couldd it be a virus if the power is off?
the only powered item is the bios
and a virus cant infect the bios

My XP Home PC strangely boots up at 12.00a.m. everyday.

Little known BIOS features: Wake up a computer on a schedule
8 Jan, 2009 Home Theatre, IMG Techie, Tips

I wanted to find a way to power on my computer at 7:30am each morning. This was so that my email and various websites I visit can be updated before I sit down at my computer. With mornings being such a rush, I wanted to use some automation to help me out.

There are NORMALLY a number of features in the power MANAGEMENT component of the BIOS options, which permit all types of triggers to wake a computer up from hibernation or standby modes. However, if the computer is turned off, these will not work.

One of the triggers allows us to set the computer to launch via the real time clock. We can set how frequently the machine will wake up, or what time of the day we want it too wake up.

Every BIOS is a little different so it is impossible to give specific instructions, but it is not too hard to find. Go into the BIOS and find Power Management. In here, ensure S3 is enabled. There should be an option called “Resume by alarm”, or “Wake-up on RTC”. Once this is enabled, you will be able to set the time you want your computer to turn on.
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