Crystal Reports prompt issue on export: "The report you requested requires further information"

Question

I have searched through forums for a solution but none seem to work for me.
I have an ASP Webform/MySql application which displays Crystal Reports.
The ones which do not require a user to enter a parameter display fine and I am able to click on export on the CR toolbar and download, e.g. .pdf format.
On the report that require a user to enter a parameter, the report renders fine but when I click on the export button, i get the prompt:
"The report you requested requires further information"
asking for DB login credentials. How can I avoid this?
My Code:
Aspx page:
<%@ Register Assembly="CrystalDecisions.Web, Version=13.0.2000.0, Culture=neutral, PublicKeyToken=692fbea5521e1304" Namespace="CrystalDecisions.Web" TagPrefix="CR" %>
<div>
          <CR:CrystalReportViewer Width="960px" ID="CrystalReportViewer1" runat="server" AutoDataBind="true" />
</div>
protected void Page_Load(object sender, EventArgs e)
         if (Request.QueryString["report"] != null)
                string reportToGet = Convert.ToString(Request.QueryString["report"]);
                switch (reportToGet)
                        case "payslip":
                        PaySlip();
                        break;
                        case "pastpayslip":
                        PanelPastPaySlip.Visible = true;
                        break;  
                       default:
                       break;
protected void btnSearch_Click(object sender, EventArgs e)
      if (txtDate.Text != null || txtDate.Text != string.Empty)
      if (DateTime.TryParseExact(txtDate.Text, "yyyy-MM-dd", CultureInfo.InvariantCulture,
      DateTimeStyles.None, out date))
      PastPaySlip();
private void PastPaySlip()
            // Some code....
            PayMasterDataSetTableAdapters.pastpayslipcasualviewTableAdapter ta =
                new PayMasterDataSetTableAdapters.pastpayslipcasualviewTableAdapter();
            PayMasterDataSet.pastpayslipcasualviewDataTable dt = new PayMasterDataSet.pastpayslipcasualviewDataTable();
            ta.FillBy(dt, userId, businessId);
            cReport = new ReportDocument();
            string reportPath = Server.MapPath("~/Views/CasualLabour/Reports/PastPaySlip.rpt");
            cReport.Load(reportPath);
            cReport.SetDataSource((DataTable)dt);
            cReport.SetParameterValue("Date", date);
            cReport.SetDatabaseLogon("userID", "password", "server", "database");
            CrystalReportViewer1.ReportSource = cReport;
            CrystalReportViewer1.ReuseParameterValuesOnRefresh = true;
I am using CR V. 13.0.9 and VS 2013 Update 2

Answer 1

This is because almost any action on the viewer result sin a postback. This includes paging, zooming, drilling exporting and printing. E.g.; you will have to place the report in session. See the following KB for how to:
1985571 - How to use sessions in web applications using the Crystal Reports viewer (the complete code)
- Ludek
Senior Support Engineer AGS Product Support, Global Support Center Canada
Follow us on Twitter