wglCreateContext throws INVALID_OPERATION exception

suppose that I have COpenGLControl class downloaded here from codeguru assuming that the first event handler runned when creating the OpenGL window is OnCreate, I have tried to catch up the errors of this class. here's the code used to create the window in my dialog's .h and .cpp files:

MyOpenGLTestDlg.h

COpenGLControl m_oglWindow;  

MyOpenGLTestDlg.cpp

CRect rect;

// Get size and position of the picture control
GetDlgItem(ID_OPENGL)->GetWindowRect(rect);

// Convert screen coordinates to client coordinates
ScreenToClient(rect);  

up to know I think the function OnCreate has been invoked. In fact, I think the line of code COpenGLControl m_oglWindow; causes this function to be invoked! but I'm not sure so it will be appreciated if you guide me alittle about this?
anyway, I have not made a lot of change to the class:

OpenGLControl.h

#pragma once
#include "afxwin.h"
#include "WinBase.h"

#include <gl/gl.h>
#include <gl/glu.h>

class COpenGLControl : public CWnd
{
public:
    /******************/
    /* Public Members */
    /******************/
    UINT_PTR m_unpTimer;
    // View information variables
    float    m_fLastX;
    float    m_fLastY;
    float    m_fPosX;
    float    m_fPosY;
    float    m_fZoom;
    float    m_fRotX;
    float    m_fRotY;
    bool     m_bIsMaximized;

private:
    /*******************/
    /* Private Members */
    /*******************/
    // Window information
    CWnd  *hWnd;     //window handle
    HDC   hdc;       //device context handle    
    HGLRC hrc;       //handle to GL Rendering Context
    int   m_nPixelFormat;
    CRect m_rect;
    CRect m_oldWindow;
    CRect m_originalRect;

public:
    COpenGLControl(void);
    virtual ~COpenGLControl(void);

    void oglCreate(CRect rect, CWnd *parent);
    void oglInitialize(void);
    void oglDrawScene(void);

    // Added message classes:
    afx_msg void OnPaint();
    afx_msg void OnSize(UINT nType, int cx, int cy);
    afx_msg void OnDraw(CDC *pDC);
    afx_msg int  OnCreate(LPCREATESTRUCT lpCreateStruct);
    afx_msg void OnTimer(UINT nIDEvent);
    afx_msg void OnMouseMove(UINT nFlags, CPoint point);

    DECLARE_MESSAGE_MAP()
};  

OpenGLControl.cpp

int COpenGLControl::OnCreate(LPCREATESTRUCT lpCreateStruct)
{
    if (CWnd::OnCreate(lpCreateStruct) == -1) return -1;

    oglInitialize();

    return 0;
}  
void COpenGLControl::oglInitialize(void)
{
    // Initial Setup:
    //
    static PIXELFORMATDESCRIPTOR pfd =
    {
        sizeof(PIXELFORMATDESCRIPTOR),
        1,
        PFD_DRAW_TO_WINDOW | PFD_SUPPORT_OPENGL | PFD_DOUBLEBUFFER,
        PFD_TYPE_RGBA,
        32, // bit depth
        0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
        24, // z-buffer depth
        8,0,PFD_MAIN_PLANE, 0, 0, 0, 0,
    };

    // Get device context only once.
    hdc = GetDC()->m_hDC;
    // Pixel format.
    m_nPixelFormat = ChoosePixelFormat(hdc, &pfd);
    SetPixelFormat(hdc, m_nPixelFormat, &pfd);
    // Create the OpenGL Rendering Context.
    hrc = wglCreateContext(hdc);
    GLenum error13 = glGetError();
    wglMakeCurrent(hdc, hrc);

   // Basic Setup:
   //
   // Set color to use when clearing the background.
   glClearColor(0.0f, 0.0f, 0.0f, 1.0f);
   glClearDepth(1.0f);
   // Turn on backface culling
   glFrontFace(GL_CCW);
   glCullFace(GL_BACK);
   // Turn on depth testing
   glEnable(GL_DEPTH_TEST);
   glDepthFunc(GL_LEQUAL);
   // Send draw request
   OnDraw(NULL);
}  

As you see I have written the code GLenum error13 = glGetError(); right after hrc = wglCreateContext(hdc); to catch any probable error that it throws and yes the value for error13 is 1282 which means INVALID_OPERATION so I think the handle for OpenGL rendering context is not created properly!
besides if you check the values for hdc and hrc, you encounter these:

hdc -> unused = ??? (Error: expression can not be evaluated)
hrc -> unused = 0

Could you help me find out why it is the case? and what's the problem?

The results are quite undefined if you call GL functions (like glGetError() itself) without having a current GL context.

wglCreateContext() is part of the Win33 API (and not the GL API) and will signal errors by returning a NULL pointer. You can call the Windows API function GetLastError() if you want details in that case, like with most other Windows API functions.