Noticed this error for the first time today running `sudo apt upgrade`. Also for the first time (single user account laptop) had to sign on to console (ctrl+alt+F1) and (ctrl+alt+f2) because Ubuntu 16.04 login screen wasn't working due to activating Nvidia 367.44 driver in `Additional Drivers` screen.
Signing into console was necessary for the first time ever in order to restore Intel integrated graphics and using the system normally.
Noticed this error for the first time today running `sudo apt upgrade`. Also for the first time (single user account laptop) had to sign on to console (ctrl+alt+F1) and (ctrl+alt+f2) because Ubuntu 16.04 login screen wasn't working due to activating Nvidia 367.44 driver in `Additional Drivers` screen.
Signing into console was necessary for the first time ever in order to restore Intel integrated graphics and using the system normally.
(Kernel version 4.7.5)