Following an outage of the public power supply my HP Compaq DX2400 (Vista) will not boot. I can access the BIOS screens and make changes if necessary but on startup the PC will only boot to the ‘starting Windows' screen and then loops back to the initial BIOS startup screen. This loops continuously. System Restore will run but then BSOD and the error message above and advising a problem relating to the page file. Safe Mode does not work and I cannot boot from CD (so I cannot use the HP recovery discs) or installed HDD. The PC is exactly as supplied by HP with no additional hardware or software installed and was working normally until the power outage.
You've done a lot of the things I was going to tell you to do, so you've effectively stolen my thunder. I do have one suggestion that it looks like you haven't tried.
Of course, a power outage can leave your operating system files corrupted or your hardware damaged. If this is the issue then you are looking at some major work to find out what the problem is. They can also corrupt the BIOS because things weren't able to shut down properly before the outage, and a simple clearing of the CMOS might do the trick.
There are two kinds of CMOS - those that come as a flat, round watch-type battery and those that are jumpers on the mother board that you can reset. I believe that yours is the jumpers on the motherboard. To reset these, turn of the PC and unplug it. Open the case and find the motherboard. You should be able to clearly see the jumper that clears the BIOS settings in CMOS RAM. Set the jumper that is labeled "Clear CMOS" to pins 1-2. Wait 10-15 seconds and then move the cap back to pins 2-3. When you start the computer you will need to enter the BIOS setup to reset any custom BIOS settings.
If you happen to have the flat, watch-battery type of CMOS, you should be able to gently pull the battery off of the motherboard, wait a few seconds and then put it back. Either method will clear the BIOS settings and should allow the computer to start up normally.
Reinstall the Operating System
I'm not sure why you can't boot from CD (I'm hoping that it's due to a BIOS problem that will reset with the CMOS), but if you still can't get out of the BSOD, then you might need to reinstall Vista. You can pull the hard drive out and use it as a slave either in a working machine or in an external hard drive to save your data before you reinstall so you won't lose anything that you haven't backed up.
I'm hoping that resetting the CMOS will do the trick. If it doesn't and you need more help, please let us know.