The GUI loads to input the decryption password, but when I type, the characters appear in the top-left of my screen, as though I was typing at a console without a command prompt.
Forcing power-off and rebooting allows access to the grub menu, from recovery mode I can type my decryption password without the GUI, and from recovery, I can resume booting.
So you don't have to use recovery mode every time:
Open a console and type the command
sudo gedit /etc/default/grub
Look for the line with
GRUB_CMDLINE_LINUX_DEFAULT="quiet splash"
and change it to
GRUB_CMDLINE_LINUX_DEFAULT=""
Then update the grub bootloader with the command
sudo update-grub
tested using Ubuntu 16.04 LTS
I have caused the same problem on my own system by using this guide: Fix low resolution grub and splash screen with Nvidia drivers on Ubuntu 14.04, which says:
Edit grub:
GRUB_GFXMODE=1280x1024
GRUB_GFXPAYLOAD_LINUX=keep
and update the bootloader
sudo update-grub
Then, create a file (named splash)
sudo nano /etc/initramfs-tools/conf.d/splash
Fill it with the following line
echo FRAMEBUFFER=y
and run the command
sudo update-initramfs -u
While @mat's answer technically worked for my (Kubuntu 17.10) system, it resulted in very poor graphic performance.
The solution that worked better for me was to uncomment the
GRUB_TERMINAL=console
line of /etc/default/grub, as it kept the boot splash almost as nice as the plymouth one, and more importantly didn't trash my graphic performance.
I had the same problem with a fresh install of ubuntu 16.04.1
For those who have the same version of ubuntu I can say that you can fix it by doing:
sudo apt-get update
sudo apt-get dist-upgrade
After the next reboot the password field is focussed an you are able to type your password.
Just performing an usual "sudo apt-get upgrade" will not work!
Hint: For those who are not familiar with "dist-upgrade": It does not upgrade to the next distribution (i.e. ubuntu 16.10). The difference between these two commands is explained here.
