Failed Attempt Error Occurs When Connecting WinForms ReportViewer to Telerik Report Server or Reporting REST Service

Environment

Product	Progress® Telerik® Reporting
Version	Q2 2012 and later
Report Viewers	WinForms

Description

When connecting the WinForms ReportViewer to Telerik Report Server or Reporting REST service, an error for a failed attempt occurs.

Error

Attempt by method 'Telerik.Reporting.Services.HttpClient.HttpRequestHelper.GetResponseFromPost(System.Net.Http.HttpResponseMessage)' to access method 'Telerik.Reporting.Services.HttpClient.HttpRequestHelper.GetResponseFromPost <T> (System.Net.Http.HttpResponseMessage, System.Collections.Generic.IEnumerable 1 <System.Net.Http.Formatting.MediaTypeFormatter>)' failed.

Cause

The WinForms ReportViewer requires Microsoft.AspNet.WebApi.Client that is suitable for .NET4.

Solution

Install the Microsoft.AspNet.WebApi.Client trough the Visual Studio Package Manager Console. For more information, refer to the article on using the WinForms Report Viewer with the Report Server.