When it comes to reported problems with font size in Outlook, most of the time the issue people are having is too small text in emails when writing a letter, replying to it or forwarding it. This problem is pretty easily fixed: just adjust zoom settings on the Reading Pane. Other times users complain that menus and/or icons are too small in Outlook on their high resolution monitors. Too small font in older programs is actually a pretty common issue with HiDPI. The solution here might lie in changing display setting for Windows or for Outlook itself. This articles describes some fixes you may try to get rid of the small font problem in Outlook.