Hello Rebecca, This sounds like something we would want to go through our support team for assistance with. However, that being said.. I am curious to know: Are both the Mac and PC devices using the same browser? (Chrome/Firefox/Opera) or Are they different? (Internet Explorer and Safari?) Is the report being exported by the same user or is it being ran as you on a PC and the other person as themselves on a mac for example? You can edit a report, go to report actions, and choose to run the report with the access rights of someone (typically this is done if a user has a need to see the report results from objects that they don't otherwise have direct access to.) Good luck! Thanks, Dustin Martin Assigned Support Engineer Workfront