header('Access-Control-Allow-Origin: *'); Not allowing CORS request

Question

I have a PHP file which generates a JSON document.

I\'ve set the header as follows but am still getting an error.

header(\'Access-Control-Al         


        

Answer 1

Such a situation may arise when an error occurs on the requested page. In this case the error page sets headers, that likely has no Access-Control-Allow-Origin header.