I'm relatively new to VB.NET programming.I am a C,C++ Programmer.but I know a little bit of VB.NET programming as I knew VB6 a little bit.

I want to use Google Earth COM API.Please give me some thought about Interfaces and Classes and how to use it for API.

My Code is :
SC.Search(src) Code:
  1. Public Class Form1
  2.     Private GE As EARTHLib.ApplicationGE
  3.     Public SC As EARTHLib.ISearchControllerGE
  4.     Private PID As Integer
  5.  
  6.     Private Sub func_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles func.Click
  7.         Dim src, dest As String
  8.         Dim prg As Boolean
  9.         Dim feature_clct As EARTHLib.FeatureCollectionGE
  10.        
  11.         GE = New EARTHLib.ApplicationGE
  12.         SC = New EARTHLib.SearchControllerGE()
  13.         src = txtsrc.Text
  14.         dest = txtdest.Text
  15.  
  16.         While StrComp(src, "") <> 0 And StrComp(dest, "") <> 0
  17.             SC.Search(src)
  18.             Do
  19.                 prg = SC.IsSearchInProgress()
  20.             Loop While prg = True
  21.             feature_clct = SC.GetResults()
  22.         End While
  23.  
  24.     End Sub
  25. End Class

This is throwing an error :
Code:
Unable to cast COM object of type 'EARTHLib.SearchControllerGEClass' to interface type 'EARTHLib.ISearchControllerGE'. 
This operation failed because the QueryInterface call on the COM component for the interface with IID 
'{524E5B0F-D593-45A6-9F87-1BAE7D338373}' failed due to the following error: Class not registered 
(Exception from HRESULT: 0x80040154 (REGDB_E_CLASSNOTREG)).
This is in the line no:
Code:
SC.Search(src)
So,plz give me necessarry suggestions.