As I write a new email, I need to apply the same formatting to the entire text. So I selected a word, which I used as a reference, and clicked on Paint Format to use the word formatting.
After that I applied to all my text and when I sent the email, the formatting went wrong, however on the screen in the New Email, the formatting seemed correct.
The formatting was simple, just one type of font and size, for all text.
Source: Calibri
Size: 12px
I hope I’ve helped.