title: Report Viewer Control (Web) Shows Blank Report
body: <p>I have a web form containing a ReportViewer control, a DIV element so I can see that the page actually renders.  I see that my page properly loads, I see the report service being accessed in Fiddler, but there is never anything displayed.</p>
  
  <p>At present, I'm using a report with static text, no queries on it, in order to ensure that I isolate the issue.</p>
  
  <p>My page is as follows:</p>
  
  <pre class="lang-xml prettyprint-override"><code>&lt;%@ Page Language="C#" AutoEventWireup="true" CodeBehind="ReportViewer.aspx.cs" Inherits="PeopleNet.Web.Views.Reports.ReportViewer" %&gt;
  
  &lt;%@ Register Assembly="Microsoft.ReportViewer.WebForms, Version=11.0.0.0, Culture=neutral, PublicKeyToken=89845dcd8080cc91"
      Namespace="Microsoft.Reporting.WebForms" TagPrefix="rsweb" %&gt;
  
  &lt;!DOCTYPE html&gt;
  &lt;html xmlns="http://www.w3.org/1999/xhtml"&gt;
  &lt;head runat="server"&gt;
      &lt;title&gt;&lt;/title&gt;
  &lt;/head&gt;
  &lt;body&gt;
      &lt;form id="form1" runat="server"&gt;
          &lt;asp:ScriptManager ID="ScriptManager1" runat="server"&gt;
              &lt;Scripts&gt;
                  &lt;asp:ScriptReference Path="~/scripts/jquery-1.7.2.js" /&gt;
                  &lt;asp:ScriptReference Path="~/scripts/fixReportViewer.js" /&gt;
              &lt;/Scripts&gt;
          &lt;/asp:ScriptManager&gt;
  
          &lt;div&gt;
              This is the report viewer page...
          &lt;/div&gt;
          &lt;rsweb:ReportViewer ID="ReportViewer1" runat="server"&gt;&lt;/rsweb:ReportViewer&gt;
      &lt;/form&gt;
  &lt;/body&gt;
  &lt;/html&gt;
  </code></pre>
  
  <p>The code to display the report is:</p>
  
  <pre class="lang-cs prettyprint-override"><code>protected void Page_Load(object sender, EventArgs e)
  {
      this.ReportViewer1.ServerReport.ReportServerUrl = ConfigurationFacade.ReportServerUri;
      this.ReportViewer1.ServerReport.ReportPath = { path to report name };
      this.ReportViewer1.ServerReport.ReportServerCredentials = new ReportServerCredentials(); // custom class implementing IReportServerCredentials as described in various places around the web, including SO
      this.ReportViewer1.ServerReport.Refresh();
  }
  </code></pre>
  
  <p>My web.config file is configured with the HttpHandlers as required:</p>
  
  <pre class="lang-xml prettyprint-override"><code>&lt;system.web&gt;
      &lt;!-- abbreviated... --&gt;
      &lt;httpHandlers&gt;
          &lt;add path="Reserved.ReportViewerWebControl.axd" verb="*" type="Microsoft.Reporting.WebForms.HttpHandler, Microsoft.ReportViewer.WebForms, Version=11.0.0.0, Culture=neutral, PublicKeyToken=89845dcd8080cc91" validate="false" /&gt;
      &lt;/httpHandlers&gt;
  &lt;/system.web&gt;
  </code></pre>
  
  <p>And :</p>
  
  <pre class="lang-xml prettyprint-override"><code>&lt;system.webServer&gt;
      &lt;!-- abbreviated... --&gt;
      &lt;handlers&gt;
          &lt;add name="ReportViewerWebControlHandler" preCondition="integratedMode" verb="*" path="Reserved.ReportViewerWebControl.axd" type="Microsoft.Reporting.WebForms.HttpHandler, Microsoft.ReportViewer.WebForms, Version=11.0.0.0, Culture=neutral, PublicKeyToken=89845dcd8080cc91" /&gt;
      &lt;/handlers&gt;
  &lt;/system.webServer&gt;
  </code></pre>
  
  <p>The server runs Windows 2008 and SQL Server 2008 R2.</p>
  
  <p>I am using the SQL Server 2012 version of the viewer, as we are in the process of updating our environments to 2012.</p>
  
  <p>I have repeatedly verified that the report is accessible from the ReportManager, with no issues whatsoever.</p>
  
  <p>I have been attempting to access this in IE9, having seen various issues stated with other browsers.</p>
  
  <p>I am presently (for testing only) passing my credentials as the report server credentials.  I am a Reporting Services Administrator, as well as a member of the server administrators group on the server.</p>
  
  <p>I have checked both the event log and the ReportServerService log, and have found nothing amiss.</p>
  
  <p><strong>UPDATE:</strong> Looks like when change the AsyncRendering to false, and ensure that I don't try to "SetParameters" with an empty collection, this gets mostly cleared up:</p>
  
  <pre class="lang-cs prettyprint-override"><code>this.ReportViewer1.AsyncRendering = false;
  </code></pre>
  
  <p>What am I missing in the configuration/code here?</p>