Missing content
When distributing a map or mod, care must be taken to ensure that any custom content (sounds, materials, textures, models, etc.) is also distributed, or else players will have an unintended experience.
- Missing materials/textures show up as a black-and-magenta checkerboard (in Counter-Strike 2, shows up as a flashing black-and-red checkerboard, Half-Life: Alyx shows up as red wireframe that flashes and Hammer, shows up as white texture, in Hammer's Texture Browser shows up as black texture with the text "No Image", and entities with missing icons in Hammer show up as Obsolete sprite).
- Missing models show up as red 3D text saying "Error" (in Portal 2 the 3D Error text is a light blue, in CS:GO since new updates shows up as big red box with ERROR text textured on it, Source 2 and Strata Source games shows the text in orange color, with Source 2 games being in a slightly different font, and Cry of Fear shows up as red text saying "Error cant find model")
- Missing sounds are absent (in Portal 2, a missing sound is indicated by Dr. Kleiner saying "Oh, fiddlesticks. What now?", and CSGO, a klaxon sound plays.)
- Missing particles (at least in Portal 2 and Team Fortress 2) appear as a spray of red X's.
- Missing animations appear as A-Pose.
If the missing contents shipped with the Source SDK, and are not custom creations, it is likely a problem with your game configuration. See Reset the Source SDK Game Configuration for more information.
Common Problems
One very common problem is when users see a black-and-magenta checkerboard/black textured "sheen" or reflection on surfaces. This is caused by a missing texture, generally due to missing cubemaps, which must be "built" in-game prior to distributing the map.