Build Error!!

Output from BUILD shown at the bottom of this message

Funny thing is the source file compiles OK. Its only when I try and BUILD the executeable.

Im a beginner at this stuff.
It looks as though it has something to do with this function:

auxDIBImageLoad(...)

AUX_RGBImageRec *CGlView::LoadBMP(char *Filename)                    // Loads A Bitmap Image
{
     FILE *File=NULL;          
     if (!Filename)                              {
          return NULL;                         }

     File=fopen(Filename,"r");              
     if (File)                              
     {
          fclose(File);
           return auxDIBImageLoad(Filename);        
     }

     return NULL;                        
}

Anyone have any ideas. I dont have a flippin clue.
================================

Linking...
GlView.obj : error LNK2001: unresolved external symbol _auxDIBImageLoadA@4
Debug/DlgOgl.exe : fatal error LNK1120: 1 unresolved externals
Error executing link.exe.

DlgOgl.exe - 2 error(s), 0 warning(s)