docamo,

You should open up your own thread instead of putting your problem on the back of a 10 months old thread by another.

I believe if you want to boot from an external hard disk you need to tell Bios the first bootable disk is the IEEE Lacie drive. You also need to put Grub on the MBR of the IEEE Lacie drive. It appears to me you have put Grub into the MBR of the internal hard disk.

Here is a temporary cure to get Windows back

(1) Restore Windows MBR to the internal disk. Task B1 or B2 of my last signature refers.

or

(2) Use another Live CD that you can boot Windows with. Details in this thread.

Run the live cd again and install Ubuntu to your external hdd.

Do not touch the boot sequence of your computer.

The GRUB mbr is cobntained in your internal hdd as far as i know but it links to the external one to run. So that means you always need your external hdd connected, even if you want to run xp!

Just re-install Ubuntu and then keep the hdd connected and reboot your computer. You should be able to select xp or ubuntu to boot into! Once you have booted into xp you can then disconnect your external hdd if you wish!

Just make sure that the boot order of your computer is set to boot from your internal hdd BEFORE it tries to boot from your external!