Thank you for your reply. ItemDataBound is a event of DataGrid and DataList, Since I am using DataGridView and developing windows application, this event is not useful.

Should I put this code in my code? If it is so, "private m_NetworkStream = new NetworkStream();" it gives compile error. Can you give detailed information please?

Thank you for your reply, I dont need internet avaliability, but it is useful. I think I can use NetworkAvailabilityChangedEventHandler, as you wrote. Thanks again;)