There are three basic sources of automatic reboot problems:
• Recovery settings
• Software incompatibilities, including driver issues
• BIOS problems
Here's a tip about searching the Microsoft Knowledge Base for information on the automatic reboot problem: Microsoft rarely, if ever, refers to a “reboot” in their Knowledge Base articles, so searching for that will yield little. Try searching with “restart” or “restarts” instead.
Recovery Settings
One of the things that is quite different about Windows XP compared to Windows 9x (9x is shorthand for Windows 95, Windows 98, and Windows Me in all their various versions), is that one can control how it responds to certain critical errors—those that cause the infamous Blue Screen of Death (BSOD). In Windows XP, the default setting is for the computer to reboot automatically when a fatal error occurs. If that fatal error only occurs when you're shutting down, the system reboots automatically.
If you haven't changed any of the system failure settings, you should be able to see the error by looking in the Event Log. But a better long-term solution is to turn off the automatic reboot so you can actually see the error when it happens—chances are it will tell you enough about itself to let you troubleshoot further. To change the recovery settings to disable automatic rebooting:
1. Right-click My Computer, and then click Properties.
2. Click the Advanced tab.
3. Under Startup and Recovery, click Settings to open the Startup and Recovery dialog box.
4. Clear the Automatically restart check box, and click OK the necessary number of times.
5. Restart your computer for the settings to take effect.
Now when you go to shut down and a fatal error occurs, you'll at least see it and it won't cause an automatic reboot. You still have to sort out what's causing the problem, but that gets us to the next section quite nicely.
Software Incompatibility
The most common cause of a fatal error or BSOD is a software or driver problem, and troubleshooting these can be tricky. The mechanism for troubleshooting, however, is pretty much the same for any problem on a PC. The first thing to look at is what's changed—what new software program or driver have you added, usually just before the problem started. This sounds easy and it often is, but if it's something you've lived with for a while, you'll often have no idea what the proximate cause is. When you do, it's a lot easier. When you don't, you need to do a bit of research to find out if there is a specific cause for the particular error message you're getting (when you have one) or a known issue with certain programs or drivers that causes the behavior you're seeing. In the case of automatic reboots, even when you've selected a shutdown, a search of the Microsoft Knowledge Base turns up
Windows XP Restarts When You Try to Shut Down Your Computer
BIOS Problems
Finally, the last and often trickiest to troubleshoot source of reboot problems: your computer's BIOS. If there is a problem in your BIOS, or sometimes even in the firmware for one of the other pieces of hardware installed in your machine, it could cause an instability and lead to one of those automatic restarts that we talked about in the first section. Especially if the problem is in the Advanced Configuration and Power Interface (ACPI) portion. The good news is that these problems are much less common than they used to be in the bad old days. But it never hurts to check with your computer manufacturer to see if there's an updated BIOS available.
