A friend of mine has a Packard Bell laptop that came with Windows pre-installed. I installed Ubuntu on it and it works fine, but everytime she tried to boot Windows on it (fortunately rarely) it fails and the computer is unable to boot any OS anymore.
Upon boot, the computer stops on a black screen with a
GRUB Rescue prompt.
Is there any way to restore GRUB without re-installing Ubuntu? (preferably an easy way as I cannot do it for her and she is not extremely computer literate)
Also (but less important), is there a way to configure GRUB (or something else) so that Windows won't destroy it on every boot attempt?