Can't Dual Boot with XP & 7

t33lo

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I previously had a partition with XP and nothing on the other partition. I installed Windows 7 onto the blank partition with no problems. After installing 7, I was prompted with which OS to boot up on in DOS.

The other day, I decided to format the XP partition and reinstall XP on it. Now, I can't get the DOS prompt to choose which OS to boot. Does anyone know how to fix this? Thank you!
 

AKM880

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Same thing happened to me, I had a 40GB HDD running Win 7 and a 250GB running Win XP. I decided to reformat the XP with Windows 7 installed on the 40GB HDD. The bad thing is that I had to reinstall Windows 7 since I couldn't boot to it. You might be able to find your documents if you go to control panel, computer management, and find the HDD's.
 

t33lo

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Yeah I think that is my last resort, but I had some important applications (not files) on that partition.


Does anyone know how to boot to it? I have tried using some boot loader programs but they aren't working properly. Thank you!
 

MrLinux

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Sounds like the MBR was on the XP partition.
In Vista you'd have to run Bootrec.exe from a recovery console, no idea if W7 has this option.
 

pat mcgroin

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Here is a excerpt from a article by Scott Dunn
It is a much longer article but I just provided what you needed.
Search the Vista forum if you want the entire article. I have posted it several times.
W7 works the same as Vista

Step 7. Your system now boots to XP, so we'll need to do some fixing to set up a boot menu. Insert your Vista DVD and restart the computer from it. Click Next in the first screen.

Step 8. Don't click Install when prompted! Instead, click Repair Your Computer in the lower-left corner.

Step 9. When the System Recovery Options dialog appears, make sure Microsoft Windows Vista is selected and click Next. In the next dialog box, select the Command Prompt option at the bottom.

Step 10. In the command-prompt window, type the following commands and press Enter after each one:

bootrec.exe /fixMBR
bootrec.exe /fixBoot

Step 11. Close the command prompt and click Restart.

Step 12. When your computer has booted into Vista, click Start, type cmd.exe, and press Ctrl+Shift+Enter to make the command window open with elevated privileges. Click Continue, if prompted by User Account Control.

Step 13. Type the following commands in the command window, one at at time, pressing Enter after each one. After each command, you should get the response, "The operation completed successfully." A response of, "The specified entry already exists," is OK, too. If not, retype your command to make sure you've entered it correctly. If Vista is installed on a drive other than c:, change the first command below to use the proper drive letter. The curly braces around {ntldr} in each command must be typed exactly as shown:

bcdedit -set {ntldr} device partition=C:
bcdedit -set {ntldr} path \ntldr
bcdedit -displayorder {ntldr} -addlast
bcdedit -set {ntldr} description "Microsoft Windows XP"

That's it! The next time you restart your system, you should be see a prompt that will let you choose between Vista or XP. Select the one you want and press Enter.
 

sturm

Splendid
When you reformatted the xp partition you wiped out the part that loaded the os choice screen. This is the only problem with dual booting is when you redo the first installed os you can't get to the newer os until after you reinstall the old one and repair the new one like mentioned above.