Hosting the Reporting REST Service in Medium Trust environment leads to a permission error.
|Product||Progress® Telerik® Reporting REST Service|
|Application Type||Web Application|
|Report Viewer||HTML5 Report Viewer|
Hosting with Medium Trust: "Request for the permission of type 'System.Security.Permissions.SecurityPermission, mscorlib, Version=18.104.22.168, Culture=neutral, PublicKeyToken=b77a5c561934e089' failed."
The Reporting REST Service is not designed to operate in Medium Trust environment.
The error will be bubbled in the web viewer's preview window when the Reporting REST service is hosted in Medium Trust environment.
Separate the Reporting REST Service and host it in an environment with Full Trust- check How To: Self Host Telerik Reporting REST Web API and How To: Add Telerik Reporting REST Web API to Web Application(you can find the VS project template in the Reporting category of VS templates). This may require you to enable CORS for the service to let the HTML5 Viewer communicate with it.