Origin is not allowed by Access-Control-Allow-Origin

I wrote an article on this issue a while back, Cross Domain AJAX. The easiest way to handle this if you have control of the responding server is to add a response header for: Access-Control-Allow-Origin: * This will allow cross-domain Ajax. In PHP, you’ll want to modify the response like so: <?php header(‘Access-Control-Allow-Origin: *’); ?> … Read more

“Origin null is not allowed by Access-Control-Allow-Origin” error for request made by application running from a file:// URL

For the record, as far as I can tell, you had two problems: You weren’t passing a “jsonp” type specifier to your $.get, so it was using an ordinary XMLHttpRequest. However, your browser supported CORS (Cross-Origin Resource Sharing) to allow cross-domain XMLHttpRequest if the server OKed it. That’s where the Access-Control-Allow-Origin header came in. I … Read more

No ‘Access-Control-Allow-Origin’ header is present on the requested resource—when trying to get data from a REST API

This answer covers a lot of ground, so it’s divided into three parts: How to use a CORS proxy to get around “No Access-Control-Allow-Origin header” problems How to avoid the CORS preflight How to fix “Access-Control-Allow-Origin header must not be the wildcard” problems How to use a CORS proxy to avoid “No Access-Control-Allow-Origin header” problems … Read more

XMLHttpRequest cannot load XXX No ‘Access-Control-Allow-Origin’ header

tl;dr — There’s a summary at the end and headings in the answer to make it easier to find the relevant parts. Reading everything is recommended though as it provides useful background for understanding the why that makes seeing how the how applies in different circumstances easier. About the Same Origin Policy This is the Same … Read more