AxWebBrowser problem

I have a form that uses an AxWebBrowser control.  However, it will not navigate to any site or local file.  What is the problem and how can I fix it?  I have tried everything.  Please help.  By the way, IDocHostUIHandler and ICustomDoc are impliemented corectly in another file in the namespace WebBrowser and Slide is a class with members and properties fileName and title.


        public class SlideView : System.Windows.Forms.Form,
                                           WebBrowser.IDocHostUIHandler
      {
#region members            
            private AxSHDocVw.AxWebBrowser browserControl;
            private Slide slide;
#endregion members

#region constructors            
            // should I Delete this constructor?
            public SlideView()
            {
                  InitializeComponent();
                  InitBrowser();
            }
            
            public SlideView(Slide slide)
            {
                  if (slide.FileName == String.Empty)
                  {
                        slide.FileName = GLOBALS._Document.MainPath + @"\Slides\" + slide.Title + ".htm";
                        System.IO.File.Create(slide.FileName);
                  }
                  
                  this.slide = slide;
                  this.Text = slide.Title;
                  InitializeComponent();
                  InitBrowser();
            }
#endregion constructors            

#region properties
            public Slide Slide {
                  get {
                        return slide;
                  }
            }
#endregion properties

#region methods
            private void InitBrowser()
            {
                  browserControl = new AxSHDocVw.AxWebBrowser();
                  
                  browserControl.BeginInit();
                  browserControl.Location = new Point(0,0);
                  browserControl.Size = this.ClientSize;
                  
                  browserControl.DocumentComplete += new AxSHDocVw.DWebBrowserEvents2_DocumentCompleteEventHandler(OnDocumentComplete);
                  
                  this.Controls.Add(browserControl);
                  browserControl.EndInit();
               
                        // this does not work for any site!!!!!! Please help.
                        object o = null;
                        browserControl.Navigate("www.yahoo.com", ref o, ref o, ref o, ref o);
            }
#endregion methods

#region autogen            
            void InitializeComponent() {
                  this.SuspendLayout();
                  //
                  // CreatedForm
                  //
                  this.AutoScaleBaseSize = new System.Drawing.Size(5, 13);
                  this.BackColor = System.Drawing.SystemColors.ActiveCaption;
                  //this.ClientSize = new System.Drawing.Size(292, 266);
                  this.Name = "SlideView";
                  this.ResumeLayout(false);
            }
#endregion autogen            
            
#region events            
            protected override void OnSizeChanged(EventArgs e)
            {
                  browserControl.Size = this.ClientSize;
            }
            
            public void OnDocumentComplete(object sender, DWebBrowserEvents2_DocumentCompleteEvent e)
            {
                  MessageBox.Show("document complete");
                  
                  ((WebBrowser.IHTMLDocument2)browserControl.Document).SetDesignMode("On");
                  
                  WebBrowser.ICustomDoc customDoc = (WebBrowser.ICustomDoc)
                                                                        browserControl.Document;
                  customDoc.SetUIHandler((WebBrowser.IDocHostUIHandler)this);
            }
#endregion events
            
            
#region DocHostUI            
            public uint ShowContextMenu(uint dwID, ref /*tagPOINT*/UtilityLibrary.Win32.POINT pPoint,
                                    [MarshalAs(UnmanagedType.IUnknown)] object pcmdtReserved,
                                    [MarshalAs(UnmanagedType.IDispatch)] object pdispReserved)
          {
                // use this code to show a custom menu
              /*const int Ok = 0;
                 Point p = new Point(pPoint.x, pPoint.y);
                  p = PointToClient(p);
                  myCustomContextMenu.Show(this, p);
                  throw new COMException("", Ok); */// HRESULT = S_OK: MSHTML won't show its menu

                  // use this code to let MsHtml shows its menu
                  System.Windows.Forms.MessageBox.Show("HI from cm");
                  const int Error = 1;
                  throw new COMException("", Error); // HRESULT = S_FALSE: MSHTML will show its menu
          }

          public void GetHostInfo(ref WebBrowser.DOCHOSTUIINFO theHostUIInfo)
          {
                  // turn three flags on
                  theHostUIInfo.dwFlags |= (uint) (/*WebBrowser.DOCHOSTUIFLAG.DOCHOSTUIFLAG_SCROLL_NO |
                WebBrowser.DOCHOSTUIFLAG.DOCHOSTUIFLAG_NO3DBORDER |
              WebBrowser.DOCHOSTUIFLAG.DOCHOSTUIFLAG_DISABLE_SCRIPT_INACTIVE |*/
              WebBrowser.DOCHOSTUIFLAG.DOCHOSTUIFLAG_DIV_BLOCKDEFAULT);
          }
   
          public void ShowUI(uint dwID,
                        [MarshalAs(UnmanagedType.Interface)] IntPtr pActiveObject,
                        [MarshalAs(UnmanagedType.Interface)] IntPtr pCommandTarget,
                        [MarshalAs(UnmanagedType.Interface)] IntPtr pFrame,
                        [MarshalAs(UnmanagedType.Interface)] IntPtr pDo) {}

          public void HideUI() {}
          public void UpdateUI() {}
          public void EnableModeless(int fEnable) {}
          public void OnDocWindowActivate(int fActivate) {}
          public void OnFrameWindowActivate(int fActivate) {}
          ///<see DocHostUIHandler.cs></see>
          public void ResizeBorder(ref /*tagRECT*/object prcBorder,
                                   [MarshalAs(UnmanagedType.Interface)] IntPtr pUIWindow,
                                   int fRameWindow) {}
   
          public void TranslateAccelerator(ref tagMSG lpMsg, ref Guid pguidCmdGroup, uint nCmdID)
          {
                  //const int Ok = 0;
                  const int Error = 1;
                  /*const int WM_KEYDOWN = 0x0100;
                  const int VK_CONTROL = 0x11;
     
                  if (lpMsg.message != WM_KEYDOWN)
              // allow message
              throw new COMException("", Error); // returns HRESULT = S_FALSE

                if (GetAsyncKeyState(VK_CONTROL) >= 0)
              // Ctrl key not pressed: allow message
                    throw new COMException("", Error); // returns HRESULT = S_FALSE

                  // disable the Ctrl-N and Ctrl-P accelerators
                  lpMsg.wParam &= 0xFF; // get the virtual keycode
                  if ( (lpMsg.wParam == 'N') || ((lpMsg.wParam == 'P')) )
                    throw new COMException("", Ok); // returns HRESULT = S_OK

                  */// allow everything else
                  throw new COMException("", Error); // returns HRESULT = S_FALSE
          }
   
          public void GetOptionKeyPath(ref string pchKey, uint dw) {}
      
          public void GetDropTarget([MarshalAs(UnmanagedType.Interface)] IntPtr pDropTarget,
                                    [MarshalAs(UnmanagedType.Interface)] ref IntPtr ppDropTarget)
          {
          }

          public void GetExternal([Out, MarshalAs(UnmanagedType.IDispatch)] out object ppDispatch)
          {
                  ppDispatch = null;
          }

          public void TranslateUrl(uint dwTranslate, string URLIn, ref string URLOut)  
            {
                  URLOut = URLIn; // add code here to modify the Url the user is trying to
                  // navigate to. Ex:
                  //      // prevent users from leaving your web site
                  //      if (URLIn.IndexOf("mywebsite.com") < 0)
                  //        URLOut = "http://www.mywebsite.com";
                  //      else
                  //        URLOut = URLIn;
          }

          public void FilterDataObject(IDataObject pDO, ref IDataObject ppDORet)
          {
                  //      return doIn;
          }
#endregion DocHostUI
      }