OpenGL DLL??

I think that my dll file has gone bad because when I am using Visual C++ and I try to link and assemble a program I get an error about how the SetPixel(); function and that the “device attached to the system is no longer functioning properly” Do I need a new dll file or is something else going bad. And I apologize if my info is not detailed enough but I have no clue as to what is going wrong.

SetPixel() ist GDI. Do not mix OpenGL and GDI, results are undefined.