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Getting System.MethodAccessException when running a web application with the HTML5 Report Viewer


Product Progress® Telerik® Reporting REST WebApi Service
Project Type Web Application
Report Viewer HTML5 Report Viewer


The above error appears on the page when running a web application with the HTML5 Report Viewer if the Microsoft.AspNet.WebApi.WebHost referenced assembly is of version older than 4.0.30506.

Error Message

System.MethodAccessException: Attempt by method 'System.Web.Http.HttpConfiguration..ctor(System.Web.Http.HttpRouteCollection)' to access method 'System.Web.Http.HttpConfiguration.DefaultFormatters()' failed.

Possible Cause

The common reason for this error is that some assemblies that are required by the Reporting ASP.NET Web API service are missing - Requirements for using Telerik Reporting REST WebAPI service.


In order to have a Web API based controller in the application, you need to install Microsoft.AspNet.WebApi.WebHost 4.0.30506 NuGet package or later.

## Notes  

If you use a newer version of Microsoft.AspNet.WebApi.WebHost (e.g. WebAPI 2) you have to redirect the System.Web.Http and System.Net.Http.Formatting to their newer version.

To do this, add the following bindingRedirects to your web.config and replace with the exact version:

<?xml version="1.0" encoding="utf-8" ?>
    <assemblyBinding xmlns="urn:schemas-microsoft-com:asm.v1">
        <assemblyIdentity name="System.Web.Http" culture="neutral" publicKeyToken="31bf3856ad364e35"/>
        <bindingRedirect oldVersion="" newVersion=""/>
        <assemblyIdentity name="System.Net.Http.Formatting" culture="neutral" publicKeyToken="31bf3856ad364e35"/>
        <bindingRedirect oldVersion="" newVersion=""/>

See Also

How To: Add Telerik Reporting REST Web API to Web Application.

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