jQuery Call to WebService returns "No Transport" error

Question

Add this: jQuery.support.cors = true;

It enables cross-site scripting in jQuery (introduced after 1.4x, I believe).

We were using a really old version of jQuery (1.3.2) and swapped it out for 1.6.1. Everything was working, except .ajax() calls. Adding the above line fixed the problem.

If your jQuery page isn't being loaded from http://localhost:54473 then this issue is probably because you're trying to make cross-domain request.

Update 1 Take a look at this blog post.

Update 2 If this is indeed the problem (and I suspect it is), you might want to check out JSONP as a solution. Here are a few links that might help you get started:

• https://en.wikipedia.org/wiki/JSON
• http://remysharp.com/2007/10/08/what-is-jsonp/
• http://www.west-wind.com/weblog/posts/107136.aspx

I had the same error on a page, and I added these lines:

<!--[if lte IE 9]>
<script type='text/javascript' src='//cdnjs.cloudflare.com/ajax/libs/jquery-ajaxtransport-xdomainrequest/1.0.3/jquery.xdomainrequest.min.js'></script>
<![endif]-->

and it finally works for me ;) no more error in IE9.

None of the proposed answers completely worked for me. My use case is slightly different (doing an ajax get to an S3 .json file in IE9). Setting jQuery.support.cors = true; got rid of the No Transport error but I was still getting Permission denied errors.

What did work for me was to use the jQuery-ajaxTransport-XDomainRequest to force IE9 to use XDomainRequest. Using this did not require setting jQuery.support.cors = true;

i solve it by using dataType='jsonp' at the place of dataType='json'