Results Report Not Appearing

I have a client who, periodically, has an issue with quiz results not appearing after the OK button is clicked on the ENTER NAME dialogue.   When I test the issue from another location it seems to work properly.  Can somebody give me any technical information about recommended browsers and/or browser settings, or flash settings, etc, that may prevent (or cause) this from happening?  Further, is the function of producing the report something built into Storyline or is it simply html?  (I understand that the report.html file handles the output).  With thanks,

Steve

p.s. The client is using PCs - not tablets, etc