Earlier today I upgraded my installation of Virtualbox on Windows 10 from 5.0.20 to 5.0.22. This also came up with an update to the guest additions which I installed into my Ubuntu 16.04 guest machine.
After a reboot Ubuntu would no longer boot and instead would flicker as it tried to change the screen resolution inside the virtual machine. This is a known problem in VirtualBox (see: https://www.virtualbox.org/ticket/15526).
I’ve managed to revert VirtualBox and the guest additions back to 5.0.20 using the following steps:
- On the host OS (in this case Windows 10) reinstall VirtualBox 5.0.20 over 5.0.22 – this was straight forward, I found the old installer in my downloads directory.
- Open VirtualBox and start the Ubuntu guest machine, immediately hold down the left shift key. This must be done before the purple splash screen.
- At the grub menu that loads select “Advanced Options for Ubuntu” and then select the second menu entry. This entry should contain the word “upstart”.
- Once Ubuntu has booted to a console, login.
- Switch to the currently installed VirtualBox guest additions install directory
cd /opt/VBoxGuestAdditions-5.0.22/
and try and run
sudo ./uninstall
I didn’t have much success with this.
- Insert the guest additions CD from VirtualBox’s top menu bar.
- Mount the CD Rom:
sudo mount /dev/cdrom /mnt/cdrom
- Switch to the cdrom directory
cd /cdrom
- Reinstall the old version of the guest additons
sudo ./VBoxLinuxAdditions.run
- Reboot Ubuntu and everything “should” be fine.