After freeze, reboot shows blackscreen with cursor

Question

I am using Ubuntu 18.04. After my Laptop froze, I hit the power button to shut it down and rebooted it. The login screen came up, I entered my credentials and then got a black screen and the cursor. Nothing more. I have been recently installing some package to use an Pinyin/ Chinese keyboard and yesterday installed some updates (but hadn't restarted until today morning). Hot button don't work and can't change to Function keys either.

Has anyone had this experience? Is there any way to restore it without losing data?

Answer 1

1. Immediately after the motherboard / computer manufacturer logo splash screen appears when the computer is booting, with BIOS, quickly press and hold the Shift key, which will bring up a GNU GRUB menu screen. With UEFI press (perhaps several times) the Esc key to get to the GNU GRUB menu screen. Sometimes the manufacturer's splash screen is a part of the Windows bootloader, so when you power up the machine it goes straight to the GNU GRUB menu screen, and then pressing Shift or Esc is unnecessary.

   The timing when to press the left Shift or Esc key can be tricky, so sometimes if you miss it you need to try it again.

   You will see a GNU GRUB menu screen that looks like this:

2. From the next screen select any recovery mode option.

3. From the Recovery Menu use the arrow keys to select network, press the Tab key to put the focus on <OK> and press Enter.

4. From the Recovery Menu use the arrow keys to select root, press the Tab key to put the focus on <OK> and press Enter.

5. Check Where can I look up my update history?, and write down every package that was updated in the last update.

6. Fix E: Unable to fetch some archives, maybe run apt-get update or try with --fix-missing?

   Up to this point you can run commands in recovery mode, but the commands that you try are not always successful because of package management issues. You can't install software or access the all the default software repositories. I recommend running the Ubuntu live USB/DVD that you used to install Ubuntu as a live session in order to check if the Ubuntu live session also freezes. This is to check the possibility that the freezing may be caused by a hardware issue.