Getting errors in console – uploading… never stops

Hi:

I contacted you via your website 5 days ago and never received a response.

I’m using the most basic shortcode [wordpress_file_upload]. I have the settings as slack as possible (the uploader is on a private page). I’ve disabled all plugins except the essential ones. My theme is LaunchPad (by LifterLMS.com).

I attempt to upload a file via the shortcode and never get to completion. I get the same console log and symptom when using the widget.

It seems your plugin may not work in a sub-domain?

Here is my console log:
POST https://www.mydomain.com/wp-admin/admin-ajax.php 400 (Bad Request)
sendfile @ wordpress_file_upload_functions.js:111
wfu_HTML5UploadFile_cont @ wordpress_file_upload_functions.js:114
wfu_HTML5UploadFile @ wordpress_file_upload_functions.js:100
WFU.uploadaction @ wordpress_file_upload_functions.js:10
clickaction @ wordpress_file_upload_functions.js:11
document.getElementById.onclick @ (index):650
(index):1 Failed to load https://www.mydomain.com/wp-admin/admin-ajax.php: No ‘Access-Control-Allow-Origin’ header is present on the requested resource. Origin ‘https://www.staging.mydomain.com’ is therefore not allowed access. The response had HTTP status code 400.

I’m very interested in purchasing Pro, but if this can’t even upload a file and I cannot get support, Pro can’t be any better.

A response would be appreciated.

Best Regards,