I have a HTML file in a course unit that wont launch

Hi Guys,

Not sure what is happening here, I have a button that launches and elearning module - HTML file has been uploaded from the Server and is within the Library.

When I preview the unit and click the button to launch I get the waiting circle and nothing happens.

I have used the exact same method in other units and am baffled why it is behaving this way.

http://teachuit.com.au/Courses/microsoft-excel-tune-up-course/units/the-ribbon-and-quick-access-toolbar/page/1#unit-page-1

Hope you can assist.

Cheers,
Kelly