The stop error screen or bug check screen commonly called the blue screen of death (also known as a BSoD, bluescreen, or "blue screen of doom.
In reality, the most common cause of blue screen errors is a device driver problem. Outdated, incorrect or corrupt drivers can cause the system to encounter a STOP error, resulting in the BSOD.
Often, if you're lucky, the problem will resolve itself with a simple reboot and you may never have to worry about it again. More typically though, the BSOD is a harbinger of trouble and you may find yourself faced with another and another until you throw up your hands in frustration... but all is not lost.
So the easiest way to try and fix a blue screen error is to reinstall and update your system's device drivers. This is if you are able to boot into safe mode (Press and hold the F8 key
during boot up). This will ensure that all driver bugs are fixed and that all hardware has the correct driver. If you know which device caused the error, you can update or reinstall that driver first. The file name in the blue screen of death can help identify the driver. Look for a file with the .SYS extension and search for that file name. There is a neat program on the net that can fix this problem, it's called DriverFinder, you can get it here
If this doesn't work or you can't think or find the corrupt driver you could use System Restore (If it is enabled) to go back to a time where you didn't get the error. To use the system restore utility, go to 'start/all programs/accessories/system tools/system restore.
Sometimes though the blue Screen of death can be caused by faulty or loose rame cards. Check that your RAM modules are inserted correctly and arn't clogged with dust.