Can't open course in offline Publish to CD format

Hello, all! We built a course for a Government client who has to offer the training offline. My course is saved on a local drive. I published to CD, zipped the file, and uploaded it to a drop box for them to access and save (email would've been preferred, but the zipped file was 57 MB - too large). When she unzips the content and clicks on the Launch_story file, she gets an error that says "Navigation to the webpage was canceled. What you can try: Retype the address." She reached out to her IT department and they said it isn't a firewall. Any ideas on fixes? I can't seem to find any by searching, and they need this up and running ASAP. Thank you!