solarbird | Re: Couple questions (Reply)

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Ok, short version: this is possible, without adding too much twitchiness into the game. There is even a semi-standardized procedure for doing it, assuming everything goes right.

Something going wrong is where the problem is, obviously.

This will require a live or install CD/usb drive for ubuntu. (No, you are not actually reinstalling Ubuntu. Or, well, you might, but not destroying the old install in the process.)
Also, I would suggest creating an image of the license partition and store it on the NTFS or EXT4 archive partition, as a just in case measure.
Basically, boot the Win8 install, nuke the existing XP partition, tell it to create new part there and install to it. reboot through first-run (because, seriously, do not fuck with first-run unless you have 37 virgin dragons to sacrifice, it will only cause headaches), and shut down. Boot from the live/install device, and try this: https://help.ubuntu.com/community/Boot-Repair . Don't even bother with any of the options, just try the recommended repair. If you need to touch the options, there are easier ways to do it. That SHOULD do it, you should be golden, and done.

If it doesn't, the easiest thing to do would be nuke the above-noted license partition, and convince ubu to do a BARE MINIMUM INSTALL onto that partition. In the process, the installer will probe for other installed OSen, and fix the bootloader into something workable. Once you got back into the good ubu install, you could nuke that temporary install, and I think all would be gravy.