How do I change the name on outgoing email

For the ten+ years I've had an .mac email address, I've used my DBA as the name on my outgoing mail. When I upgraded to Yosemite, it changed it to the name on my credit card. I went and edited it on "manage your Apple ID," and it allowed me to change it. However, it has had no effect on my outgoing mail. This is infuriating.

Suggestion?

Thanks

DLS