Hi,

Sorry for the late reply here. This is a tough one.

After a long day of debugging and researching, the conclusive answer I have here is that it seems like your server is not responding with the correct header from the ajax request. The ContentType is missing from the respond, and that subsequently causes the browser/javascript to not read the response properly.

A quick search on Google shows this: http://www.whote.info/blog/2013/01/06/implementing-content-type-header-on-nginx/

It seems like on nginx, you will need to add a code to the server configuration. You might want to consult your hosting provider regarding this.