Storyline Course not loading in IE11

I have uploaded a course to our server and tested the course through IE11 and it has worked perfectly for me (except the occasional jumping of slides), but the main issue at the moment is that some staff members aren't able to open the course at all. They just get the whirling grey circle that just never loads the course. I also am having issues with opening in Chrome, so am really stuck with what i am suppose to do when some staff can access the course and others cant. Help :)