When you restart your computer or upgrade to Windows XP, you receive the "STOP 0x000000ED UNMOUNTABLE_BOOT_VOLUME" error message

When you first restart your computer during the upgrade to Windows XP, or when you start Windows XP, you may receive the following error message: Note In this error message, aaaaaaaa, bbbbbbbb, cccccccc, and dddddddd are hexadecimal numbers that may vary.

If you receive this error message when you restart the computer for the first time during an upgrade to Windows XP, your original operating system will still work correctly. In some cases, you may see a message that states that the wrong cable is being used. However, you may not see this message on computers that have a fast startup time.

Advanced troubleshooting

These methods are intended for advanced computer users. If you are not comfortable with advanced troubleshooting, you might want to ask someone for help, use the Microsoft Customer Support Services Web site to find other solutions, or contact Support. See the "Next steps" section for more information about the Microsoft Customer Support Services Web site.

Begin by reading the "Technical information about the error" section to understand why the error might be generated and the purpose of the message. Otherwise, you can skip this information and begin with "Method 1: Check the error message" to help you resolve the issue.

Technical information about the error

This section provides some technical background about the cause of this error message and why it might be generated.

This behavior can occur if either of the following conditions is true:

• Your computer uses an Ultra Direct Memory Access (UDMA) hard disk controller, and the following conditions are true:
  • You use a standard 40-wire connector cable to connect the UDMA drive to the controller instead of the required 80-wire, 40-pin cable.
  • The basic input/output system (BIOS) settings are configured to force the faster UDMA modes.
• The file system is damaged and cannot be mounted.

The purpose of this error message is to prevent the following two things:

• Potential data loss caused by using an incorrect IDE cable for the faster UDMA modes. An IDE cable is a kind of cable used to connect storage devices, such as hard disks, inside a computer.
• Continued access to a drive on which the file system is damaged

Method 1: Repair the volume

Note the second parameter (0xbbbbbbbb) in the error message. You might have to regenerate the error in order to write it down.

If the second parameter (0xbbbbbbbb) of the Stop error is 0xC0000032, the cause of the error is that the file system is damaged. You can try to repair the volume to see whether this resolves the error. If the second parameter is not 0xC0000032, see "Method 2: Check the IDE cable and load Fail-Safe settings" for help.

Some things that you should know before you try this solution

• If the file system is damaged, you can use chkdsk /r command to repair the volume. However, if you use the chkdsk /r command, you may lose some data.
• You will need the Windows startup disks or the Windows installation disk. If you do not have them, contact the computer manufacturer for help in obtaining the disks.
• You will need the administrator password to complete the steps.

To repair the volume, follow these steps:

1. Start your computer by inserting the Windows startup disks or the Windows installation disk if your computer can start from the CD drive.
2. When the Welcome to Setup screen appears, press R to select the repair option.
3. If you have a dual-boot or multiple-boot computer, select the Windows installation that you want to access from the Recovery Console.
4. Type the administrator password when you are prompted to do this.
   
   Note If no administrator password exists, press ENTER.
5. At the command prompt, on the drive where Windows is installed, type chkdsk /r, and then press ENTER.
6. At the command prompt, type exit, and then press ENTER to restart your computer.
7. After you repair the volume, check your hardware to isolate the cause of the file system damage.

If this procedure does not work, repeat it, but type fixboot instead of chkdsk /r in step 5.

If you are still unable to resolve the issue, please see the "Next steps" section for help.

Method 2: Check the IDE cable and load Fail-Safe settings

If your computer uses a UDMA hard disk controller, try these steps. If your computer does not use a UDMA hard disk controller, see the "Next steps" section for help.

• If your UDMA hard disk is connected to the controller with a 40-wire UDMA cable, replace the cable with an 80-wire cable.
• In the BIOS settings for your computer, load the 'Fail-Safe' default settings, and then reactivate the most frequently used options, such as USB Support.

If you are not sure how to follow these steps, contact the manufacturer or refer to the user’s guide that was included with your hardware.

If these methods did not help you resolve your issue, you can use the Microsoft Customer Support Services Web site to find other solutions to your problem. Some services that the Microsoft Customer Support Services Web site provides include the following:

• Searchable Knowledge Base (http://support.microsoft.com/search/?adv=1) : Search technical support information and self-help tools for Microsoft products.
• Solution Centers (http://support.microsoft.com/select/?target=hub) : View product-specific frequently asked questions and support highlights.
• Microsoft Customer Support Newsgroups (http://www.microsoft.com/communities/newsgroups/default.mspx) : Contact counterparts, peers, and Microsoft Most Valuable Professionals (MVPs).
• Other Support Options (http://support.microsoft.com/default.aspx?pr=csshome) : Use the Web to ask a question, contact Microsoft Customer Support Services, or provide feedback.

If you continue to have problems after you use these Microsoft Web sites or if you cannot find a solution to the problem on the Microsoft Support Services Web site, click the following link to contact Support.

For more information about how to use the Recovery Console in Windows XP, click the following article number to view the article in the Microsoft Knowledge Base: For more information about how to create a multiple-boot system in Windows XP, click the following article number to view the article in the Microsoft Knowledge Base: For more information about the "STOP 0x000000ED UNMOUNTABLE_BOOT_VOLUME" error message in Windows XP, click the following article numbers to view the articles in the Microsoft Knowledge Base: