แย่แล้วครับ ลง Windows ใหม่แล้ว Error ถึง Code ของผมจะหน้าตาแปลกๆ แต่เคยใช้ได้จริงๆครับ แต่พอลง Windows ใหม่แล้ว Error เลย

        Dim intNumRows As Integer
        Dim connection As String = "Data Source=.\SQLEXPRESS;AttachDbFilename=|DataDirectory|\Database.mdf;Integrated Security=True;User Instance=True"
        Dim sqlroom As String
        Dim conn As New SqlConnection(connection)
        conn.Open()
        sqlroom = "SELECT COUNT(*) FROM RESV WHERE ROOM_ID = '" & DropDownList1.SelectedValue & "' AND Convert(DateTime, '" & Me.CalendarPopup1.SelectedDate & "', 103) BETWEEN DATE_FROM AND DATE_TO AND Convert(DateTime, '" & Me.CalendarPopup2.SelectedDate & "', 103) BETWEEN DATE_FROM AND DATE_TO "
        Dim ccommand As New SqlCommand(sqlroom, conn)
        intNumRows = ccommand.ExecuteScalar()
        If intNumRows > 0 Then
            Label1.Text = "NO"

        Else
            sqlroom = "SELECT COUNT(*) FROM RESV WHERE ROOM_ID = '" & DropDownList1.SelectedValue & "' AND DATE_FROM BETWEEN Convert(DateTime, '" & CalendarPopup1.SelectedDate & "', 103) AND Convert(DateTime, '" & CalendarPopup2.SelectedDate & "', 103) AND DATE_TO BETWEEN Convert(DateTime, '" & CalendarPopup1.SelectedDate & "', 103) AND Convert(DateTime, '" & CalendarPopup2.SelectedDate & "', 103) "
            Dim bcommand As New SqlCommand(sqlroom, conn)
            Dim intNumRows2 As Integer
            intNumRows2 = bcommand.ExecuteScalar()
            If intNumRows2 > 0 Then
                Label2.Text = "NO"
            Else
                Dim com As New SqlCommand(sqlroom, conn)
                Dim dr As SqlDataReader = com.ExecuteReader
                GridView1.DataSource = dr
                GridView1.DataBind()
                dr.Close()
                conn.Close()
            End If
        End If
    End Sub