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I have my Ubuntu installed on a USB drive, and to log into Windows I need to have it plugged while booting, or I get the Grub rescue prompt.

When the USB drive is plugged in, I get the Grub menu from which I can choose Windows.

Ubuntu 13.04 on the USB, Windows Vista on :C

jasonwryan
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Borgia
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  • @railgun - the *best way* could be debatable - but are you booting from an UEFI system or BIOS. My money's on UEFI, and, in that case, I would argue that you should remove `grub` completely - especially with a USB install. – mikeserv Dec 29 '14 at 23:41

1 Answers1

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You installed the first stage grub loader to the mbr of the hardrive and put the rest of grubs files in your boot partition on the usb drive. To do what you want you need to put grub onto the mbr of the usb drive, repair the mbr of the windows drive (vista equivalent of fdisk /mbr) and change your boot order to boot from usb first, if present, then hard disk.

hildred
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