Cannot Load HTML5 Report Viewer Templates

Environment

Product	Progress® Telerik® Reporting
Version	Q2 2012 and later
Report Viewers	WinForms, WPF, ASP.NET

Description

An Error loading the report viewer's templates. (Template = /api/reports/resources/templates/telerikReportViewerTemplate-html) occurs when using the HTML5 Telerik Reporting ReportViewer.

Cause

The error message indicates that the Reporting REST service is not responding.

Solution

To solve the issue, use the following approaches:

• Check the HTML5 Viewer serviceUrl and adjust the relative path.
• Try adding ~ or removing the first ..
• It is recommended to test the service by address in the browser as described in the article on adding the Telerik Reporting REST web API to web applications.
• The issue might be related to duplicating routes of the WebAPI controllers. To avoid such a possibility, change the Telerik Reporting REST Web API routes registered byu default.