title: error LNK2001: unresolved external symbol
body: <p>I am receiving this error </p>
  
  <pre><code>&gt;GXRenderManager.obj : error LNK2001: unresolved external symbol "private: static class GXRenderer * GXRenderManager::renderDevice" (?renderDevice@GXRenderManager@@0PAVGXRenderer@@A)
  </code></pre>
  
  <p>The following is my code...</p>
  
  <h2>GXDX.h</h2>
  
  <pre><code>class GXDX: public GXRenderer {
  public:
      void Render();
      void StartUp();
  };
  </code></pre>
  
  <h2>GXGL.h</h2>
  
  <pre><code>class GXGL: public GXRenderer {
  public:
      void Render();
      void StartUp();
  };
  </code></pre>
  
  <h2>GXRenderer</h2>
  
  <pre><code>class GXRenderer {
  public:
      virtual void Render() = 0;
      virtual void StartUp() = 0;
  
  };
  </code></pre>
  
  <h2>GXRenderManager.h</h2>
  
  <pre><code>#ifndef GXRM
  #define GXRM
  #include &lt;windows.h&gt;
  #include "GXRenderer.h"
  #include "GXDX.h"
  #include "GXGL.h"
  
  enum GXDEVICE {
      DIRECTX,
      OPENGL
  };
  
  class GXRenderManager {
  public:
      static int Ignite(GXDEVICE);
  
  private:
      static GXRenderer *renderDevice;
  
  };
  
  #endif
  </code></pre>
  
  <h2>GXRenderManager.cpp</h2>
  
  <pre><code>#include "GXRenderManager.h"
  
      int GXRenderManager::Ignite(GXDEVICE DeviceType)
      {
          switch(DeviceType)
          {
          case DIRECTX:
              GXRenderManager::renderDevice = new GXDX;
              return 1;
              break;
          case OPENGL:
              GXRenderManager::renderDevice = new GXGL;
              return 1;
              break;
          default:
              return 0;
          }
      }
  </code></pre>
  
  <h2>main.cpp</h2>
  
  <pre><code>#include "GXRenderManager.h"
  
  int WINAPI WinMain(HINSTANCE hInstance, HINSTANCE hPrevInstance,
      LPSTR lpCmdLine, int nCmdShow)
  {
      return 0;
  }
  </code></pre>
  
  <p>I am not trying to get it to do anything. I am just trying to compile with no errors. I am new with all this so if anyone can give me a hand. that will be great. thanks</p>