Remove ViewState from ASPX Page.

Just Copy/Paster following Code in your Code.

 

Protected Overrides Function LoadPageStateFromPersistenceMedium() As Object

        Return (New LosFormatter().Deserialize(DirectCast(Session("ViewState"), String)))

    End Function

    Protected Overrides Sub SavePageStateToPersistenceMedium(ByVal state As Object)

        Dim los As New System.Web.UI.LosFormatter()

        Dim sw As New System.IO.StringWriter()

        los.Serialize(sw, state)

        Dim vs As String = sw.ToString()

        Session("ViewState") = Nothing

        Session("ViewState") = vs

    End Sub