'Open a Rich Text File:
Try
Dim dlg As OpenFileDialog = New OpenFileDialog
dlg.Title = "Open"
dlg.Filter = "Rich Text Files (*.rtf)|*.rtf"
If dlg.ShowDialog() = System.Windows.Forms.DialogResult.OK Then
RichTextBox1.LoadFile(dlg.FileName)
End If
Catch ex As Exception : End Try