How to fix error "Xlib: extension "NV-GLX" missing on display"?

When I try to confirm than I can run Unity 3D on my Asus U31SD with intel's i5 Sandy Brigde and Nvidia 520 and Nvidia Optimus I receive this error: Xlib: extension "GLX" missing on display ":0".

Of course, I cannot run any of the effects of Ubuntu 11.10, not even the simple app switcher.

Can anybody help me? Thank you

Solution 1:

This error occurs when you install the proprietary nvidia driver on NVidia Optimus laptop. The nvidia card cannot directly be used due to the Optimus design. To repair this, uninstall the nvidia-current package and re-login. After that, you'll solely be running off the Intel graphics card which renders the nvidia card unused though it'll still be using power. Bumblebee allows you to switch off the card, see Is a NVIDIA GeForce with Optimus Technology supported by Ubuntu?

Solution 2:

If I remember well GLX have something to do with OpenGL windowsing in X systems. So make sure you install mesa package which is implementation of OGL in Linux