Hi friends!!! I have a strange problem when using OpenGL, using Dev-C++ (gcc) or Visual C++ (6.0). I haven''t posted this on the OpenGL API forum because it''s not a problem from the API. Maybe I haven''t set up something correctly. The problem appears compiling code where appears this functions (for example, maybe there are others...): gluPerspective@32, glLoadIdentity@0, glMatrixMode@4, glViewport@16. The error over Dev-C++ appears defined as : [Linker error] undefined reference to `InitializeOpenGL(int, int)''. The error over VC6 appears defined as: GLInit.obj : error LNK2001: unresolved external symbol _gluPerspective@32 Help will be very apreciatted ... Greetings, Jacob. PS: This files are always included : #include <windows.h> #include <gl/gl.h> #include <gl/glu.h> #include <gl/glaux.h>