After several days of troubleshooting, I'm trying to figure out why Steam games that use Proton suddenly stopped opening on Linux Mint 22.3. Non-Steam Windows programs launched through Bottles generally work, but Proton games do not. I suspect a graphics-driver or 32-bit library problem, although I'm not certain.
My system has an NVIDIA GeForce RTX 2070 using proprietary driver 595.91.07, along with Intel integrated graphics and llvmpipe. Steam detects the NVIDIA GPU as the default device. I have already enabled the i386 architecture and installed or checked `libnvidia-gl-595:i386`, but the issue remains.
The most relevant Proton log messages are:
`err:winediag:nodrv_CreateWindow Application tried to create a window, but no driver could be loaded.`
`err:winediag:nodrv_CreateWindow The explorer process failed to start.`
The games are installed on a separate ext4 partition mounted under `/mnt/...`, not on a drive carried over from another operating system. I also completely reinstalled the game I'm using for testing, but it still will not launch. Steam itself starts normally and reports that fsync is running. What should I check next to determine whether this is a Vulkan/NVIDIA setup problem, a Proton prefix issue, or something related to the separate game-storage mount?
2 Answers
That Wine message usually means the Windows process could not create a graphical window, but it does not by itself prove that the 32-bit NVIDIA package is missing. I’d check Vulkan outside Steam first: run a Vulkan diagnostic such as `vulkaninfo --summary` and verify that both the 64-bit and 32-bit NVIDIA Vulkan libraries are installed. Also check that `nvidia-smi` works and that the game is not being forced onto the Intel GPU or llvmpipe.
For testing, try a brand-new Proton prefix with a stable Proton version rather than Experimental, and remove any custom launch options such as `PROTON_LOG=1` after collecting the log. If every Proton title fails while Vulkan is broken, reinstalling Proton prefixes will not fix the underlying driver problem. The normal Steam startup messages, theme warning, and `XOpenIM()` errors are generally unrelated to games failing to launch.
The drive format is worth checking because Proton prefixes and symlinks can behave badly on some filesystems, especially NTFS. In this case, though, the games are on ext4, which is the expected setup, so the storage filesystem is unlikely to be the cause. Since the partition is mounted separately, it would still be useful to confirm that it is mounted with normal read/write permissions and that the user owns the Steam library directory.
The library is on an ext4 partition, mounted read/write. The games were installed there directly under Linux rather than copied from an older installation.
Steam identifies the RTX 2070 as the default GPU, and the proprietary driver is installed. I have not yet confirmed the complete Vulkan 32-bit setup or tested a fresh prefix with a stable Proton release, so those are the next checks I’m planning to make.