Hi, I used X-Plane 10 and it worked fine many times, but suddenly (I think after trying to install Paris environment) it started to crash on startup giving There was a problem processing a GLSL pixel shader. You may need to rerun the installer or update your graphics drivers. Resources//shaders/terrain_vert.glsl Resources//shaders/terrain_frag.glsl I reinstalled and updated X-Plane many times, and as there are currently no updates available for my graphics drivers, I tried to start X-Plane using the no_glsl option. I read (http://forums.x-pilot.com/topic/2349-odd-x-plane-start-up-problem/ ) that this should work fine, but in particular, X-Plane-32bit.exe --no_glsl | more gives Found sim dataref sim/time/local_time_secFound sim dataref sim/cockpit2/clock_timer/local_time_hoursFound sim dataref sim/cockpit2/clock_timer/local_time_minutesFound sim dataref sim/cockpit2/clock_timer/local_time_secondsFound sim dataref sim/graphics/misc/light_attenuationFound sim dataref sim/graphics/animation/draw_light_levelFound sim dataref sim/weather/temperature_sealevel_cFound sim dataref sim/graphics/animation/draw_object_xFound sim dataref sim/graphics/animation/draw_object_zStarting thread loader.Lighting slot 14,0 is unused.Lighting slot 15,0 is unused.Lighting slot 14,1 is unused.Lighting slot 15,1 is unused.Lighting slot 7,5 is unused.VRAM needed: 2069064. Trivial VRAM: 4054272. Packed VRAM: 2359296.Packed efficiency: 0.876984. Unpacked efficiency: 0.510342.Resources/shaders/terrain_frag.glsl: Fragment shader failed to compile with thefollowing errors:Compiler error: unexpected operatoResources/shaders/terrain_vert.glsl+Resources/shaders/terrain_frag.glsl: Fragment shader(s) were not successfully compiled before glLinkProgram() was called. Link failed. as command line output. The no_glsl option doesn't seem to influence this at all (I get exactly the same output without this option). Maybe this is due to using the x86-version (the command line options aren't included yet? --help works fine)?