How to stop Outlook from automatically marking emails as read

A reader asks: "Is there a way to stop Outlook from automatically marking every email you look at as read? Often, I scan through emails very quickly to make sure that there is nothing that requires immediate attention. Because I still need to go back and read them carefully, I don't want them marked as read. This is even more of an issue when I'm working on a project with a shared email; if one of us looks at an email, it's simply marked as read so the other person can easily miss it." There isn...