How do i prevent duplicated in combobox ?
Private Sub ComboBox1_KeyPress(ByVal sender As Object, ByVal e As
System.Windows.Forms.KeyPressEventArgs) Handles ComboBox1.KeyPress
       If Asc(e.KeyChar) = Keys.Enter Then
           AxWebBrowser1.Navigate(ComboBox1.Text)

           Dim bFound As Boolean
           bFound = False
                           For i As Integer = 0 To
ComboBox1.Items.Count - 1
                   If ComboBox1.SelectedItem = ComboBox1.Text Then
                       bFound = True
                       Exit For
                   End If
               Next
               If bFound = False Then
                   ComboBox1.Items.Add(ComboBox1.Text.ToString)
               End If
                  End If
   End Sub