I'm building a website in Angular 4.  

My url server side (Web Api) was <http://localhost:55499/api>
My url client side is <http://localhost:4200>.  

And it worked well.  

For various reasons I changed the url server to <http://localhost/AAA/api/> and I start to use iis express instead local iis.  

And since then it has stopped working.  

Brings the following error:  

> 
> No 'Access-Control-Allow-Origin' header is present on the requested resource. Origin '<http://localhost:4200>' is therefore not allowed access.
> 
> 
> 

The response had HTTP status code 400.

I have in my response `Access-Control-Allow-Origin:http://localhost:4200`

I have in the controller:

`[EnableCors(origins: "http://localhost:4200", headers: " * ", methods: " * ")]`

I use IIS EXPRESS.