Data fetch error in ReportViewerWebPart actions' menu.

I've created the application page with panel. Button_click handler adds ReportViewerWebPart to panel's controls. When I clicked "Actions" I've got this message: "An error has occurred with the data fetch.  Please refresh the page and retry".

Button_Click code:

void createChartButton_Click(object sender, EventArgs e)
        {
            ReportViewerWebPart rwp = new ReportViewerWebPart();
            rwp.Height = "1000";
            rwp.Title = "";
            rwp.ToolBarMode = ToolBarDisplayMode.Full;
            rwp.ToolBarItemsDisplayMode = ToolBarItem.Export | ToolBarItem.Print | ToolBarItem.Zoom;
            rwp.AutoGenerateTitle = false;
            rwp.AutoGenerateDetailLink = false;
            rwp.KeepSessionAlive = false;
            rwp.ScrollBars = ScrollBars.Vertical;
            rwp.AsyncRendering = false;
            rwp.ReportPath = "Shared Documents/Categories.rdl";

            ReportParameterDefaultCollection parameters = rwp.OverrideParameters;

            parameters.Add(new ReportParameter("StartDate", StartDate.SelectedDate.ToString()));
            parameters.Add(new ReportParameter("EndDate", EndDate.SelectedDate.ToString()));
            Content.Controls.Add(rwp);
        }

How can I resolve this problem?

Thanks.