Since Comcast Infinity changed their format, I've been getting emails from almost everyone that I can't read. I'm using a pretty new (last year) iMac OS Sierra. I've never had this issue before.
It was also happening on emails I was composing, but I reset the default font to Arial.
I forwarded the emails I couldn't read to my wife's MacBook Pro and there was no issue.
I spent about a half hour with Comcast tech support, they tried a few things, but couldn't help.
What's going on?