Windows XP won’t boot
If you’ve worked with windows for 2 minutes you’ve probably been exposed to the Blue Screen of Death or BsD. Usually Blue Screens are rather harmless and go away after a reboot. But when they don’t, when they stick around and keep reoccurring after every reboot, then you have problems. The first thing you should do is try to boot into safe mode. You can do this by pressing F8 after you hear your computer beep while it is booting up. If it boots into safe mode all is well and good and you just have a start-up program gumming up your computer. (See my Spyware Removal Guide for information on how to manage start-up entries.) If safe mode generates the same blue screen you have more work ahead of you.
If you can’t boot into Windows XP, not even into safe mode, and you’re getting a message like, “unmountable boot volume” on the blue screen they a simple chkdsk might fix the problem. The tricky part is booting your computer so you can run chkdsk. The easiest way to do that is to use a windows installation CD. To do boot off of a CD you first need to configure your BIOS to look for an Operating System on the CD before it tries the hard drive. Usually this is done by pressing ‘del’, ‘F2’, or some other key to enter setup and adjusting the boot priority so that the CDROM is first. When Windows setup finally loads (it takes several minutes) all you have to do is press ‘r’ to enter the recovery console.
Sometimes it will prompt you for the administrator’s password. Most people I encounter don’t know this or think they don’t have one. See the Password Recovery Guide to find out how you can reset your administrator password.
Once you are in the recovery console you will be greeted with a friendly command prompt. The first thing you are going to want to try is chkdsk. Simply typing “chkdsk” should scan your hard drive and fix any problems it finds. Sometimes it is necessary to use “chkdsk /p” and if you want to be really thorough and have several hours to burn you can use “chkdsk /r” that causes it to do a surface scan of the disk. If chkdsk get’s hung up for more than an hour, as in the percent complete doesn’t change for a long time, there is most likely something physically wrong with your hard drive it will have to be replaced. Once chkdsk complete restart the computer by typing “exit” and see if windows will boot now.
If windows still doesn’t boot go back to the recovery console and run “fixboot.” fixboot will copy certain files needed for your hard drive to boot onto your hard this will fix the problem if your computer was complaining about a missing ntldr or something like that. If fixboot doesn’t fix the problem then you should try fixmbr. fixmbr recreates the master boot record of your drive, it usually is only needed if you installed some other boot loader like grub and you want to revert back to using just Windows XP. However sometimes the master bot record becomes corrupt and it is necessary to restore it using fixmbr.
If you are getting black screens with messages like “Windows could not start beacuse following file is missing or corrupt \windows\system32\config\system” then you have a registry problem. Also if you are getting Blue screens with the stop 0x0000007E or similar messages then you might be able to fix by restoring your registry using the recovery console. Microsoft wrote a very nice article on how to do this called How to recover from a corrupted registry that prevents Windows XP from starting It involves booting in to the recovery console as described above and copying the registry files from a backup.
If windows still does not boot after using all the above methods then you’ll probably need to reinstall it. There are basically two ways to do this, a repair install or a new install. A repair install is usually preferred because it does not reset your settings or programs, the registry remains intact for the most part and when it is finished your computer will work just like it did before. With a new install windows will be like a blank slate and you probably have to reinstall most of the programs that were previously installed. Both of these can be done without loosing any information. To do a repair install you need the same edition of Windows XP that is installed on the computer. So if you have Windows XP Home you need the Windows XP Home disc or the repair install will not be an option for you.
If you are still getting blue screens or other errors after doing a reinstall of windows I would verify the integrity of my hard drive. There are many ways of doing this and most hard drive manufactures provide diagnostic software on their website. OEMs such as Dell have their own diagnostic software that they ship with their systems. However, there is an option that works with any system and any hard drive, that is the Ultimate Boot CD or UBCD. You can download it at the ultimate boot cd website.
If at this point you are sure your hard drive is functional and windows XP still does not boot you will need to reinstall windows.
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