Få Catch ex As Exception til at lave en fejl

Hej hvordan kan jeg lave en fejl så jeg kan se at dette virker

Catch ex As Exception
            Console.WriteLine(ex.Message)

Min kode er:
    Public Sub OpenDB()
        Dim ObjConn As OleDbConnection
        Dim ObjCmd As OleDbCommand
        Dim ObjReader As OleDbDataReader

        Try
            Dim ConnectionString As String = ConfigurationManager.ConnectionStrings("ConnectionString").ConnectionString
            ObjConn = New OleDbConnection(ConnectionString)
            ObjCmd = New OleDbCommand("select * from somestuff where status='MAYBE' order by date desc", ObjConn)
            ObjConn.Open()
            ObjReader = ObjCmd.ExecuteReader(CommandBehavior.CloseConnection)
            If ObjReader.HasRows() Then
                Repeater1.dataSource = objReader
                Repeater1.databind()
            Else
                Response.Write("intet i databasen DB")
            End If
        Catch ex As Exception
            Console.WriteLine(ex.Message)
        Finally
            ObjReader.Dispose()
            ObjConn.Dispose()
        End Try
    End Sub