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GRUB complains of “no such partition” after installing 12:04
My HP Pavilion All-in-One pc has a dual boot with the original Windows 7 Home premium dual booted with Ubuntu 11.10. Whilst booted in Ubuntu I upgraded to 12.04 and whilst everything seemed to install OK when it was finished and rebooted I was not presented with the normal grub screen but with a 'GNU GRUB version 1.99-21ubuntu3' screen that gave me options to Linux 3.2.0-23generic-pae and several others including 'Windows 7 (loader) (on /dev/sda1)'. However, regardless of which option I choose it comes back with 'error: no such partition'
I assume that the GRUb is pointing to the wrong place or corrupt. Any ideas how to rectify this and get me back to a bootable system?