html5 course not opening when published

For clients to access our courses, I publish the course to my local drive, then copy the files to a network drive, create a link, and send the link to clients.

The courses I'm currently working on contain videos (mp4 files).  I would like the videos to have a progress bar, so the client can move to any point in the video, so I'm publishing using the HTML5/SWF. If I double-click the index.html file, it opens correctly with the playback option in the video. However, if I click the link that we would give to clients, the course never loads, I get the loading icon and nothing happens. The odd thing is this works for HTML5 courses I developed in an older version of Captivate. I'm currently using Captivate 9.  Any suggestions on how I can fix the issue of the HTML5 version not loading or, use the swf version but add the desired playback control to the mp4?