How do I fix filesystem_steam and vgui2_s module load failures when the Linux client is starting?
If the Steam client is unable to load filesystem_steam.so or vgui2_s.so when starting up it will have to exit as these modules provide key functionality. These load failures often indicate a system configuration issue and are most easily diagnosed in a terminal window.
In a terminal window go to your Steam directory (if you have run Steam the location will usually be recorded at ~/.steam/bin32). Use the ldd command to get information on the module that couldn't load. For example, if the load of vgui2_s.so failed do this in the terminal window:
LD_LIBRARY_PATH=. ldd vgui2_s.so
If any of the lines say 'not found' or some sort of error that indicates a dependency of the module which cannot be satisfied. Correcting the problem with that dependency will likely allow Steam to work properly.
Additionally, if you have disabled the use of the Steam runtime by setting STEAM_RUNTIME=0 please enable it before troubleshooting as we want to diagnose problems with the runtime to expose problems in the runtime.