Open Mail
Preferences > Accounts
and change the Full Name on the account you are using to the name that you want to appear.
P
I have just switched from a PC to a Macbook and it has 10.6 Snow Leopard. I set up the mail app and I can send and receive email. However, the outgoing mail shows the sender as 'my name (my email address)' and I want to change it to 'My business name (my email address)'. I can find the specs in a properties tab. The 'change mailbox name' is greyed out in the Mailbox drop down box.
Thanks

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