<system.webServer> 

 <httpProtocol> 

 <customHeaders> 

 <add name="Access-Control-Allow-Origin" value="*" /> 

 <add name="Access-Control-Allow-Headers" value="Content-Type" /> 

 <add name="Access-Control-Allow-Methods" value="GET, POST, PUT, DELETE, OPTIONS" /> 

 </customHeaders> 

 </httpProtocol>

</system.webServer>