Ok, so our company has started sending PDF files to an attorney's office. We are running on all Windows based machines and they run on all Mac machines. When the file comes in, they are all showing up as zip files instead of pdf's that they can open right up. Is there any way to get these files to just show as the PDF that they came in as so they can just open the file from the email instead of having to unzip them? Also, if there isn't a way to do this, what is the best zip app to unzip these files that is free? Thanks!