Linux - User not authorized to run the X server, aborting
You're trying to launch X the same way you always have, but today of all days, you're getting the following error:
X: user not authorized to run the X server, aborting.
The first thing to check is to make sure you are not currently in an attached screen session! screen -ls You may or may not see active screens in the list, but none of them should say €śattached!€ť If it does, you're currently in a screen session, and cannot start an X session from it. Either detach your current session (screen -d) or exit out of it completely (Ctrl+A, D).
If that doesn't work, the next thing you can do is check your /etc/X11/Xwrapper.config.
sudo nano /etc/X11/Xwrapper.config
Make sure the line allowed_users is set to allowed_users=console. This means that anybody who is actively logged in to the terminal can start an X session. Don't set it to anybody unless you have a good reason to you'd be allowing anybody to start X with root privileges, and for security's sake we don't want to do that (at least without a good reason).