Http error 403 when publishing to

I created an HTML5 game, and tried to publish it to and kongregate, but when I start the game there, it says:
“Downloading failed:
HTTP error 403 on file KlingzHtml5-HTML5-Shipping.js”

On, they say this can be caused either by using abosulte paths, or by mismatched cases when referencing files.
I understand that, but have no idea how to fix it in Ue4, or the generated files.
Can anyone help?