When you are using Outlook for Microsoft 365, you can click on the percentage indicator next to the slider (in this case 100%) to set a persistent zoom factor by enabling the option Remember my preference. You can also zoom via the zoom slider in the bottom right corner. Depending on your mouse/scroll sensitivity you might need to scroll quite a bit before the font size will change. You can use CTRL+Mouse Scroll in the Reading Pane to zoom in and out per message. There are several ways to enlarge the font in the Reading Pane in Outlook Method 1: Zoom in on the message
The downside of this is that your font might become really small and hard to read which is anything but relaxed for your eyes. Using a high resolution has the benefit of a sharper display which is more relaxed for your eyes. Is it possible to enlarge the display of a received email either in the Reading Pane or after opening it? We use Outlook and my employer has trouble reading some email that is displayed on his hi-res monitor because the font sizes display so small.
