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Troubleshooting Report Server for .NET


Product Progress® Telerik® Report Server for .NET


The Report Server for .NET application can stop working for a variety of reasons such as installation failures, user permissions, IIS bindings, corrupted storage, etc.

By enabling logging, the internal exceptions that are not shown on the browser page can be seen and used to resolve the issue.


  1. Ensure that the ASP.NET Core Module (ANCM) is installed on the machine with the Telerik Report Server for .NET - Install ASP.NET Core Module (ANCM).
  2. Check for errors in the Browser Console or failing requests in the Network tab.
  3. Use Fiddler to see the exact requests from the Report Viewer of the Report Server Manager to the Report Server REST Service, and the corresponding responses - they may indicate what has failed.
  4. Enable ASP.NET Core Module logging in the Report Server for .NET application by editing the web.config file in the root directory of the application, e.g. C:\Program Files (x86)\Progress\Telerik Report Server\Telerik.ReportServer.Web.NET.

    <?xml version="1.0" encoding="utf-8"?>
    <location path="." inheritInChildApplications="false">
            <add name="aspNetCore" path="*" verb="*" modules="AspNetCoreModuleV2" resourceType="Unspecified" />
        <aspNetCore processPath="dotnet" arguments=".\Telerik.ReportServer.Web.Core.dll" stdoutLogEnabled="true" stdoutLogFile=".\logs\stdout" hostingModel="inprocess" >
                <handlerSetting name="debugFile" value=".\logs\aspnetcore-debug.log" />
                <handlerSetting name="debugLevel" value="FILE,TRACE" />
  5. Use the Event Viewer to inspect Application Event Logs of the Telerik Report Server for .NET application - Application Event Log (IIS). The events can be saved into evtx files by right-clicking on the events in the Event Viewer -> Save Selected Events.... 1 Run the app at a command prompt to catch start-up errors that may not be part of the Application Event log by executing dotnet Telerik.ReportServer.Web.Core.dll in the root directory of the Telerik Report Server for .NET - C:\Program Files (x86)\Progress\Telerik Report Server\Telerik.ReportServer.Web.NET.

If the problem persists, you may open a support ticket and send us in an archive (ZIP/RAR file) the SAZ file recorded by Fiddler, as well as the .log and .evtx files. Including the steps which have to be followed in order to reproduce the issue may speed up the diagnostic process.

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