Since you mention updating yesterday, you may want to start here to rule this problem out:
If needed, do Ctrl-Alt-F2
for a tty, then update, and reboot.
EDIT: corrected link to proper message, for clarity
Since you mention updating yesterday, you may want to start here to rule this problem out:
If needed, do Ctrl-Alt-F2
for a tty, then update, and reboot.
EDIT: corrected link to proper message, for clarity