Cannot type disk decryption password during boot

Question

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.

Solution

So you don't have to use recovery mode every time:

1. Open a console and type the command

   sudo gedit /etc/default/grub
   

2. Look for the line with

   GRUB_CMDLINE_LINUX_DEFAULT="quiet splash"
   

3. and change it to

   GRUB_CMDLINE_LINUX_DEFAULT=""
   

4. 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:

1. Edit grub:

   GRUB_GFXMODE=1280x1024
   GRUB_GFXPAYLOAD_LINUX=keep
   

2. and update the bootloader

   sudo update-grub
   

3. Then, create a file (named splash)

   sudo nano /etc/initramfs-tools/conf.d/splash
   

4. Fill it with the following line

   echo FRAMEBUFFER=y
   

5. and run the command

   sudo update-initramfs -u
   

Comments

[jaywink]

Same problem on 15.10, kernel 4.2.0-26