Using older versions of Outlook for Mac for personal email and calendar
Hello JohnRowlay,
According to my tests, the feature to don’t automatically mark items as read is available in Outlook Web App(OWA) and Outlook for Windows desktop client. However, it is not available in Outlook for Mac client. After searching in the Outlook for Mac UserVoice forum, I have found a similar feature request. You can vote here to submit your feedback: Disabling automatically marking the first e-mail as read on start-up.
You can also create a new thread in the UserVoice forum for feedback. It’s a good place for customers to share their feedbacks. Your understanding and cooperation would be highly appreciated.
Regards,
Rick