I''m having a problem when my application is run from a desktop which is pallettized (eg. 256 colour mode) My code checks the current display mode (EnumDisplaySettings), and if necessary changes the display mode to a high colour mode (eg. 16 bit), but then the call to ChoosePixelFormat fails. Interestingly enough, the code works fine if the desktop starts in a high-colour mode. The exact same thing happens if you run any of the NeHe tutorials - if you''re desktop is in 256 colour mode and you run the tutorial (selecting Yes to run in full screen mode), the program fails when calling ChoosePixelFormat. Anybody know why ? Thanks in advance.