<system.webServer> <httpProtocol> <customHeaders> <add name="Access-Control-Allow-Origin" value="*" /> <add name="Access-Control-Allow-Headers" value="Content-Type" /> </customHeaders> </httpProtocol> </system.webServer> <system.web.extensions> <scripting> <webServices> <jsonSerialization maxJsonLength="1024242"></jsonSerialization> </webServices> </scripting> </system.web.extensions>