That happened because Windows XP uses the (old) NTLDR while Windows Vista/Windows 7 use the Windows Boot Manager to load the operating system; upon Windows XP's installation, NTLDR replaced the Windows Boot Manager due to a lack of forward compatibility.
The resolve the issue, insert your Windows 7 DVD, restart your computer, and press any key to boot from CD/DVD when prompted. (You may have to edit your BIOS settings to set your optical drive as your primary boot device.) Once the Windows 7 installer launches, proceed through the keyboard/language selection and, instead of clicking Install Now, choose "Repair my Computer" from the bottom left corner. Finally, choose the Startup Repair option and restart your computer once it completes. Alternatively, boot into Windows XP and install VistaBootPRO, using it to forcefully reinstall the Windows Boot Manager and, if necessary, recreate the operating system entries.
NOTE: Both methods will result in Ubuntu being unbootable unless/until you reinstall GRUB.
Hope this helps,
John
hi,i'm using lenovo thinkpad which had come pre-installed with windows vista sp1 in C drive. a few days back i installed windows 7 on my d drive .but i planned of experimenting with my laptop by triple booting with windows xp ,( i know it sounds foolish,but that's what i did)in my e drive...after installing xp i couldn't boot into vista or seven,,so i installed ubuntu in my e drive so that i could boot to vista or seven through grub,,but after installing ubuntu ,to my surprise the windows boot manager didn't contain any entries of vista or seven,so now i'm stuck with linux and can't boot to windows,,
PLEASE HELP!!I NEED TO BOOT TO WINDOWS!!
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