The fonts that show up through Internet Explorer are based on the fonts that are installed on your computer. So, while I'm at work, many peoples' signature fonts don't show up correctly (are seen as a default font, usually Arial) but when I'm at home they show up just fine in the correct font because I have more "fun" fonts installed on our home computer.
As far as AOL goes, that's a whole different entity in itself--I'll never really understand AOL--so I can't help you there!
ETA: When in doubt, try restarting your computer. That's our mantra at work. If that doesn't work, throw something at it.
