We need more details.
You switched operating systems, but how is Steam set up? Flatpak? Package mamager?
How are your drives set up? What file systems? Where are your games installed? Any of those games have Linux versions that don't need Proton?

Try clicking on settings for the individual games and choosing compatibility, not just the global steam settings… I’m not sure the latter is needed at all.

Don't use NTFS.

More information is needed.

How is Steam installed?
Are you only using Mint or are you dual booting?
What drive are you launching and installing your games from?
Did you format the drive to be compatible with Linux first?

You must reinstall games on external drives if you previously installed them while you were a Windows user. As in, you can't install games on an external drive with Windows then switch your OS to Linux and still launch those games. You have to reinstall them from your Linux version of Steam.

If you're not dual booting than more than likely the drive that you keep your games on is formatted incorrectly as an NTFS and a simple reformat to Ext4 or another format that works with Linux will fix this problem.

NTFS doesn't play nice with Linux.

Clearing the Cache from within the settings in the Steam client has worked for me in the past. As others have said, not sure on your setup ie dual booting and whether your games are on a NTFS formatted drive.

when Installing games under Linux then Proton does the magic to translate between what Windows binarys expects and what Linux can provide.

This means that alongside what Steam under Linux installs is not just the game itself... it installs the correct Wine/Proton environment for that game as well...

This is why you just can't keep your old NTFS partition with your Steam library and expect it to simply work under Linux.

And do not use NTFS (a Windows file system) under Linux... now a days Linux can read/write to NTFS partitions but the file permissions between NTFS and for example ext4 is completly different... sure... NTFS has filepermissions as well... but they are NOT compatible at all...

Here is the "I just switched over from Windows" package to fix all common mistakes. Work through this from top to bottom:

Make sure i386 architecture is enabled. Run:
If it does not print "i386" run this:

For Ubuntu: Look at /etc/apt/sources.list.d/ubuntu.sources and compare. Only the URIs may differ:
Copy and paste if it differs.

For Mint: Look at /etc/apt/sources.list.d/official-package-repositories.list and compare. Only the URIs may differ:
Copy and paste if it differs.

Update your system. Run:

Start App Center (on Ubuntu) or Software Manager (on Mint), search for Steam and uninstall. Then run cleanup:

Install newest kernel. Very important for AMD cards, optional for Nvidia but still recommended. Run:

If i386 architecture was missing and you have an Nvidia card the driver has to be reinstalled from scratch. First uninstall:
Install nvidia driver (only if you have an Nvidia card):

If i386 architecture was missing and you have an AMD card the driver has to be reinstalled from scratch. First uninstall:
Install AMD driver (only if you have an AMD card):

Install vulkan-tools to check GPU availability and driver:

Install correct Steam package:

Reboot the PC and run vulkaninfo:
Your GPU should be listed and have deviceType PHYSICAL_DEVICE_TYPE_DISCRETE_GPU.

Now start Steam.

Make sure that your Steam library is on an ext4 partition. Check partition types with:
Reformat with gparted if necessary (tutorials on Youtube).

After that everything should run smoothly.

Should you run into GPU issues with newly released games try the Mesa PPA:
Please sanity check the packages before installing. It should only upgrade packages, not replace or remove them.

If your games run slow, disable your integrated GPU in the BIOS.

If your game still doesn't start or it uses the wrong GPU, run:
Then find the correct GPU in the list. After "GPU N:" there will be two number groups separated by a colon for every GPU. Copy the number and use it when launching Steam:
If you want the setting permanent, edit /usr/share/applications/steam.desktop and change:

Great, extensive advice from Yoth above. Excellent tips.


If you feel lost, you who are reading this. For Mint, this should be enough:


If you already have Steam installed, uninstall it in the same way you installed it then:

su -l
(l=L)
dpkg --add-architecture i386
apt-get update
apt-get upgrade
apt-get install steam
exit


or (the same commands written in a different way):

sudo dpkg --add-architecture i386
sudo apt-get update
sudo apt-get upgrade
sudo apt-get install steam


if there is no package named steam in Mint, check what name it has:

su -l
(l=L)
dpkg --add-architecture i386
apt-get update
apt-get upgrade
apt-get install steam
(no package)
apt search steam
apt-get install steam-installer
exit



If you feel lost and do not know how and which NVIDIA driver package you should install:

https://wiki.debian.org/NvidiaGraphicsDrivers
(Find your graphics card in - supported devices, and follow the instructions)

did u format the drive to ext4 or generally anything that is NOT ntfs and how did u install steam?

Steam is really bad at giving you launch errors, so you should either open the console-log file inside the steamroot/logs folder or open steam with the terminal by typing in

Format the drive your games are on to the same format as drive your operating system is on.
Literaly took me a week of scouring the internet to find the issue and it's the easiest thing to overlook as a noob. Don't give up tho