Hi I recently updated my files and didn't check what I installed so now when it boots up it says Failed to start the X server (your graphical interface). It is likely that it is not set up correctly. Would you like to view the X server output to diagnose the problem?"
The next window would show me more info, then I get
"The X server is now disabled. Restart MDM when it is configured correctly. What's up with that?

Maybe this would help?

When I type and entered the copy part from one thing to the other it said permission denied.


Wait is that sudo cp part all together with the previous lines?

What distribution of Linux are you running btw, Ubuntu/Linux Mint/Fedora/etc?

Xserver display issues are kind tricky to diagnose remotely.
Just from what has mentioned in your posts, after doing system updates you need to make sure the MDM service is enabled + set to run at system boot. systemctl start + systemctl enable probably have to be reset on that MDM service

Linux mint

Try running the updates again.

sudo apt update
sudo apt upgrade
sudo apt dist-upgrade

I've never actually had to try it, but can't you roll back now? There is a program called Timeshift, which should make backups of your system once a day -- depending on how it is set up. It wasn't on the older Linux Mint versions, so depends what you actually have.

Doesn't Linux Mint allow you to boot from an older kernel at the power up prompt?
have you tried loading a older kernel bootimage and seeing if the Xserver issue goes away?

How do I do that?

This link shows you what the menu looks like/where it appears (right after Bios/uefi).
https://linuxmint-installation-guide.readthedocs.io/en/latest/boot_options.html

Isn't the Xorg config file unnecessary now? As in Xorg detects the hardware and makes it work fine most of the time?

If necessary, you could boot from live distro (and mount your home directory) to keep the computer as a bit more useful.

Anyway, take a look at Xorg's log file. Mine are located at
~/.local/share/xorg/
but I don't run Mint. Look at the date of those files and pick the most recent one.

its very difficult to lose your files in linux. as long as you the memory, you can copy your home dir, paste and merge it into the new install if you end up reinstalling. try to keep the same username, at least until you have your files back. unless you want to deal with permissions.

The OP is using Linux Mint, no idea what version of Mint/what LinuxMint GUI is in place on their system beyond a Xserver/MDM setup mentioned in their original post.
An update happened on the OP's system, but since the OP isn't sure what was updated, it's really hard to help them out.

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Emachine9643

Booting to a Mint Live Distro, suggested by Gede was a good idea. Would add plug in a USBstick and backup any $HOME user files just in case a total system wipe/Mint reinstall ends up being the easiest/fastest fix.