Solution 1 of 5 - Run Startup Repair (Vista/2008)

Windows Vista/2008 offer a semi-automatic way to fix a range of startup and file problems.

1. Boot from your bootable Vista/2008 installation DVD and go into the Vista Recovery Console.
2. At the System Recovery Options menu, select Startup Repair.
3. Remove the DVD and select the Restart button.

With luck this will correct the problem.

Solution 2 of 5 - Repair File System (XP/2003)

You'll use the Recovery Console to check and fix file system problems. To get to the Recovery Console prompt. insert the XP installation CD and reboot the system. Assuming the BIOS defaults to booting from the media (usually the default) a "Welcome to Setup" screen appears. Press R to load the Recovery Console.

At the prompt, type:  chkdsk /r

For detailed instructions with screen shots to run the recovery console, go to Using System Restore XP/2003

Solution 3 of 5 - Repair Damaged or Missing OS Files

Use the Windows RE (Repair Environment) under Vista to repair and replace missing or damaged files. For XP users, you can re-install XP without erasing applications or settings, or use the XP Recovery Console to fix some problems.Using Windows RE for Vista/Server 2008

For detailed instructions with screen shots, go to Using System Restore Vista/2008, or use the brief summary here:

You'll need the Vista installation DVD. Note that many OEM manufactures leave out the installation DVD, which has to be purchased separately, or they only include a limited restore DVD that just erases the system and starts over (often a poor choice). All retail copies of Vista include this bootable DVD.

Insert the DVD and reboot the system. Assuming the BIOS defaults to booting from the DVD (usually the default) then select the language. Next click on Repair your computer. A list of Vista installations should appear. Select your installation (typically there will only be one).

A list of recovery options will appear including an automatic repair function, restore from a previous system restore point, restore the computer from a backup (assuming one is available), run the memory diagnostic tool, or go to a command prompt (for advanced users).

As a reminder, not all hal.dll files are the same and if the system was using a different version or one provided by the PC manufacturer that is different than the one you copied, it may cause odd behavior and/or hang at a later point.

Reinstalling XP without erasing settings and applications

Windows XP recovery is more problematic with a number of issues, including having the right media (SP1, SP2, SP3) on hand. You can usually re-install XP without erasing your applications and settings. We'd also recommend backing up all your important data before starting just to be safe, although this can be difficult if the system isn't working!

You'll need the XP installation CD. Note that many OEM manufactures leave out the installation media, which has to be purchased separately, or they only include a limited restore CD that just erases the system and starts over (often a poor choice). All retail copies of XP include this bootable media.

Insert the CD and reboot the system. Assuming the BIOS defaults to booting from the media (usually the default) a "Welcome to Setup" screen appears.

Press Enter (DO NOT select Recovery Console). Accept the license agreement. It will then search for existing XP installations and show a list to pick from (typically there will only be one choice). Select your XP installation and press R to start the repair.

Important: If the R option does not appear, do not select Enter or all your data and applications will be toast as it acts like a new PC installation!

Limited Fixes with the XP Recovery Console

For detailed instructions with screen shots, go to Using System Restore XP/2003, Here you can fix registry problems, missing files, validate and fix file system problems, repair the Master Boot Record (MBR) and partition boot record.

To get to the Recovery Console prompt. insert the XP installation CD and reboot the system. Assuming the BIOS defaults to booting from the media (usually the default) a "Welcome to Setup" screen appears. Press R to load the Recovery Console.

Solution 4 of 5 - Fix Boot.ini (XP/2003)

If the Boot.ini file points off to the wrong partition or drive, this error can occur.

If you have Fix-It Utilities Professional or SystemSuite Professional, we suggest using it's BOOT.INI repair tool as it is much faster and deals with some special situations. Simply boot from the Rescue CD or diskette and at the menu, select BootFixer. Remove the CD and select Exit.

To fix Boot.ini using the Windows boot CD:

1. Boot from your bootable XP/2003 installation CD and go into the XP Recovery Console. Follow our guide and you'll end up at a command prompt.
2. At the prompt, type: bootcfg /rebuild
3. This will locate any XP installations and display them. At the prompt Add installation to boot list? enter Y and press Enter.
4. Next it asks for you to enter the text to use for the OS Enter Load Identifier. For example type Windows XP Professional and press Enter.
5. One last prompt asks you to Enter OS Load Options. Type /Fastdetect and press Enter. (View Boot.ini options at Microsoft).
6. Remove the boot CD and type Exit and press Enter.

If the BOOT.INI was the cause of the problem, Windows will boot normally.

Solution 5 of 5 - Fix Missing or Damaged ntoskrl.exe File

You can use Windows Recovery Console to fix a missing or damaged ntoskrnl.exe file. First boot from your Windows boot CD/DVD. We recommend you use a version that matches the OS service pack installed on your system (i.e. if you have Vista SP1, use a Vista SP1 DVD).

For Vista/2008, go to the page Vista Recovery Console . Using the option "Startup Repair" should take care of it.

For XP/2003, go to the page XP Recovery Console . You'll need to go through the command prompt and expand and copy the ntoskrnl.ex_ file from the CD to  WindowsSystem32 toskrnl.exe. Instructions are in the XP Recovery Console guide, under Fix a Damaged or Missing File.

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