machine froze during upgrade to 12.04

Solution 1:

The original poster here, SplashHit, indicated in a comment that this question on SuperUser answered the question.

  • In that question, the OP followed this "guide" posted on Launchpad (which is actually the original version of this bug report by TJ).

  • rumtscho, the OP of that SuperUser question, had attempted to chroot into the installed system from a live CD system and run dpkg --configure -a, but there were lots of Permission denied error messages.

  • The accepted answer (by Darth Android) was that the OP needed to mount the /proc and /dev filesystems in the chroot before running dpkg ....

It's unclear from SplashHit (the original poster here)'s comment whether the Launchpad "guide" was sufficient to solve this problem here, or if the answer to that question was also necessary.

In any case, it appears that this question is now effectively answered for the OP (and abandoned).

@SplashHit, if I am mistaken and you still need help with this problem, please let us know (you can post a comment here, and of course if there is additional information then you can add that to your question).

Solution 2:

Try holding down Shift to get to the GRUB2 menu. If that works, see if you can boot any of the options. (You can then provide more information in your question.)

If that doesn't work, or you do get a GRUB2 menu but you can't boot into Ubuntu, try reinstalling the GRUB2 boot loader to your Master Boot Record (MBR), using any of these methods.

Once you've booted into Ubuntu, you can attempt to repair and finish the upgrade by running sudo apt-get dist-upgrade.