GRUB2 failed with 'No video mode activated'

Solution 1:

Basically, Grub2 is trying to load some fonts and cannot because they are located on the encrypted partition.

The bugreport + fix are located here :

FIX on comment #24 from Guido Nickels https://bugs.launchpad.net/ubuntu/+source/grub2/+bug/699802

If you don't want to scroll, just cut & paste :

sudo cp /usr/share/grub/*.pf2 /boot/grub/ && sudo update-grub

Hope this helps

In the file /etc/default/grub find and turn off (comment with "#") two lines:

GRUB_HIDDEN_TIMEOUT=0
GRUB_HIDDEN_TIMEOUT_QUIET=true

After this run update-grub. This method together with the previous advice of jflaflamme was helped me.