I don’t recall having this problem before Office 365 (eg: Microsoft Office 2013 & 2016), but recently noticed my text-only emails were being displayed in the Calibri font 🤮

Most of my plain-text email come in as system-generated plain-text notifications and a fixed-width font simply makes them easier to read.

Here is how to adjust those settings…

File > Options > Mail > Stationery and Fonts

Under “Composing and reading plain text messages” change the font to your desired fixed-width of preference.

My go-to is Courier New 10pt on a 1920×1080 resolution display. Simply tweak the font settings for the desired display result.

You may need to switch which email you’re viewing between adjustments as this did not update on-the-fly when I was changing them for the selected email message 😉