I have a page with a single ReportViewer (v.15) that shows a report, the loading routine resides in Page_Load inside an if (!IsPostBack) block, and like always in debug everything works just fine. But when I publish it onto a remote server running IIS 10 I'm getting a constantly loading report, with a single exception in console as follows:
I've found that for some reason when report loads and posts back to get the data the IsPostBack stays false effectively reloading the report. After digging it for two days I've found this answer, then seen this one and tried to switch the Application Pool Mode to classic, and everything started to work as expected. I believe it's some kind of misconfiguration, but I can't find what and where.
Bellow is relevant parts of code and configuration:
Default.aspx
<%@ Page Title="Test Report" Language="C#" MasterPageFile="~/Site.Master" AutoEventWireup="true" CodeBehind="Default.aspx.cs" Inherits="Reporting._Default" %>
<%@ Register assembly="Microsoft.ReportViewer.WebForms, Version=15.0.0.0, Culture=neutral, PublicKeyToken=89845dcd8080cc91" namespace="Microsoft.Reporting.WebForms" tagprefix="rsweb" %>
<asp:Content ID="BodyContent" ContentPlaceHolderID="MainContent" runat="server">
<rsweb:ReportViewer ID="ReportViewer" runat="server" EnableTelemetry="false" height="980" width="800" ShowExportControls="true" ShowPrintButton="true" AsyncRendering="true" SizeToReportContent="true">
</rsweb:ReportViewer>
</asp:Content>
Site.Master
<%@ Master Language="C#" AutoEventWireup="true" CodeBehind="Site.master.cs" Inherits="Reporting.SiteMaster" %>
<!DOCTYPE html>
<html lang="en">
<head runat="server">
<meta charset="utf-8" />
<meta http-equiv="X-UA-Compatible" content="IE=edge" />
<meta name="viewport" content="width=device-width, initial-scale=1.0" />
<title><%: Page.Title %> :: SSRS</title>
<asp:PlaceHolder runat="server">
<%: Scripts.Render("~/bundles/modernizr") %>
</asp:PlaceHolder>
<webopt:bundlereference runat="server" path="~/Content/css" />
<link href="~/favicon.ico" rel="shortcut icon" type="image/x-icon" />
</head>
<body>
<form runat="server">
<asp:ScriptManager ID="ScriptManagerMaster" runat="server">
<Scripts>
<%--To learn more about bundling scripts in ScriptManager see https://go.microsoft.com/fwlink/?LinkID=301884 --%>
<%--Framework Scripts--%>
<asp:ScriptReference Name="MsAjaxBundle" />
<asp:ScriptReference Name="jquery" />
<asp:ScriptReference Name="bootstrap" />
<asp:ScriptReference Name="respond" />
<asp:ScriptReference Name="WebForms.js" Assembly="System.Web" Path="~/Scripts/WebForms/WebForms.js" />
<asp:ScriptReference Name="WebUIValidation.js" Assembly="System.Web" Path="~/Scripts/WebForms/WebUIValidation.js" />
<asp:ScriptReference Name="MenuStandards.js" Assembly="System.Web" Path="~/Scripts/WebForms/MenuStandards.js" />
<asp:ScriptReference Name="GridView.js" Assembly="System.Web" Path="~/Scripts/WebForms/GridView.js" />
<asp:ScriptReference Name="DetailsView.js" Assembly="System.Web" Path="~/Scripts/WebForms/DetailsView.js" />
<asp:ScriptReference Name="TreeView.js" Assembly="System.Web" Path="~/Scripts/WebForms/TreeView.js" />
<asp:ScriptReference Name="WebParts.js" Assembly="System.Web" Path="~/Scripts/WebForms/WebParts.js" />
<asp:ScriptReference Name="Focus.js" Assembly="System.Web" Path="~/Scripts/WebForms/Focus.js" />
<asp:ScriptReference Name="WebFormsBundle" />
<%--Site Scripts--%>
</Scripts>
</asp:ScriptManager>
<div class="container body-content">
<asp:ContentPlaceHolder ID="MainContent" runat="server">
</asp:ContentPlaceHolder>
<hr />
<footer>
<p>SSRS</p>
</footer>
</div>
</form>
</body>
</html>
Web.config:
<system.web>
<compilation targetFramework="4.8">
<buildProviders>
<add extension=".rdlc" type="Microsoft.Reporting.RdlBuildProvider, Microsoft.ReportViewer.WebForms, Version=15.0.0.0, Culture=neutral, PublicKeyToken=89845DCD8080CC91" />
</buildProviders>
<assemblies>
<add assembly="Microsoft.ReportViewer.Common, Version=15.0.0.0, Culture=neutral, PublicKeyToken=89845DCD8080CC91" />
<add assembly="Microsoft.ReportViewer.WebForms, Version=15.0.0.0, Culture=neutral, PublicKeyToken=89845DCD8080CC91" />
<add assembly="Microsoft.ReportViewer.ProcessingObjectModel, Version=15.0.0.0, Culture=neutral, PublicKeyToken=89845DCD8080CC91" />
<add assembly="Microsoft.ReportViewer.WebDesign, Version=15.0.0.0, Culture=neutral, PublicKeyToken=89845DCD8080CC91" />
<add assembly="Microsoft.ReportViewer.DataVisualization, Version=15.0.0.0, Culture=neutral, PublicKeyToken=89845DCD8080CC91" />
<add assembly="Microsoft.ReportViewer.Design, Version=15.0.0.0, Culture=neutral, PublicKeyToken=89845DCD8080CC91" />
<add assembly="Microsoft.ReportViewer.WinForms, Version=15.0.0.0, Culture=neutral, PublicKeyToken=89845DCD8080CC91" />
</assemblies>
</compilation>
<httpHandlers>
<add path="Reserved.ReportViewerWebControl.axd" verb="*"
type="Microsoft.Reporting.WebForms.HttpHandler, Microsoft.ReportViewer.WebForms, Version=15.0.0.0, Culture=neutral, PublicKeyToken=89845DCD8080CC91" validate="false" />
</httpHandlers>
</system.web>
<system.webServer>
<validation validateIntegratedModeConfiguration="false" />
<modules runAllManagedModulesForAllRequests="true">
<remove name="TelemetryCorrelationHttpModule" />
<add name="TelemetryCorrelationHttpModule" type="Microsoft.AspNet.TelemetryCorrelation.TelemetryCorrelationHttpModule, Microsoft.AspNet.TelemetryCorrelation" preCondition="managedHandler" />
<remove name="ApplicationInsightsWebTracking" />
<add name="ApplicationInsightsWebTracking" type="Microsoft.ApplicationInsights.Web.ApplicationInsightsHttpModule, Microsoft.AI.Web" preCondition="managedHandler" />
</modules>
<handlers>
<add name="ReportViewerWebControlHandler" verb="*" path="Reserved.ReportViewerWebControl.axd" preCondition="integratedMode"
type="Microsoft.Reporting.WebForms.HttpHandler, Microsoft.ReportViewer.WebForms, Version=15.0.0.0, Culture=neutral, PublicKeyToken=89845DCD8080CC91" />
</handlers>
</system.webServer>
I tried to remove parts of Web.config that belong to Classic Mode (the httpHandlers, validateIntegratedModeConfiguration and runAllManagedModulesForAllRequests) but it didn't help...
