"The disk drive for / is not ready yet or not present" message on boot

After upgrading my Ubuntu machine from ver. 11.10 to 12.04, I get the following error and the machine stop working before any graphical environment:

** (plymouthd:357): WARNING **: Command line `dbus-launch --autolaunch=530c973a1fe4d1e1e6bd... 
--binary-syntax --close-stderr' exited with non-zero exit status 1: Autolaunch error:
X11 initialization failed.\n
udevd[397]: specified group 'colord' unknown
The disk drive for / is not ready yet or not present.
Continue to wait, or Press S to skip mounting or M for manual recovery.

Any help appreciated.

Solution 1:

I think I had the same problem going from 10.04 to 12.04.1. Here is how I fixed it. During the upgrade the packages got all messed up and when it rebooted it came up with the "Disk Dirve for / not ready".

I pressed M to go in to manual recovery.

Turns out the root partition was mounted read only. So I remounted as readwrite by

chroot /
mount -n -o remount,defaults /dev/sda1 /

Then to fix the broken packages I did a

apt-get install -f

The upgrade then proceeded and all seems okay now. Phew (for me anyway).