When attempting to run various pieces of software (notably Steam and Yenka), I have come across an error similar to this: enter code here error while loading shared libraries: libGL.so.1: cannot open shared object file: No such file or directory I'm running a 64 bit system, with an NVidia Optimus card (I dual boot for certain windows only software that requires a dedicated graphics card). I have bumblebee installed, and I am using the nvidia-current driver, rather that one downloaded from NVidia, as recommended. The library (libGL.so.1) is not present in the top directory of /usr/lib, however it is present in /usr/lib32/nvidia-current, as a softlink to /usr/lib32/nvidia-current/libGL.so.304.64. A section of the output from ldconfig -p: libGL.so.1 (libc6,x86-64, OS ABI: Linux 2.4.20) => /usr/lib/x86_64-linux-gnu/mesa/libGL.so.1 libGL.so (libc6,x86-64, OS ABI: Linux 2.4.20) => /usr/lib/x86_64-linux-gnu/libGL.so libGL.so (libc6,x86-64, OS ABI: Linux 2.4.20) => /usr/lib/x86_64-linux-gnu/mesa/libGL.so Obviously a library with that name is being loaded, but they are located in /usr/lib/x86_64-linux-gnu, however installed software doesn't seem to able to 'see' it. For Steam, running it with optirun causes it to work, but this is not the case for Yenka. I assume that optirun causes the library stored in /usr/lib32/nvidia-current to be used, which allows Steam to run, so I can't understant why Yenka won't run. Can anyone explain why software can't see the normal mesa library, and why Yenka refuses to run with the nvidia-current library?