What are the
Sender's Name and Address appear on my Outgoing Messages?
The Information of the Sender's Name and Email Address in fact are
displayed after logging into WebMail 2.0 as the screen is shown
below:

1. By default, the Sender's Name will be set to the User Name
of your account. You can change it by modifying the value of Name
field in the Personal Information Options.
2. By default, the Account-Username Address will be set as the
Sender Email Address for outgoing email. However, if you have
already registered an Email Alias for your account, you can change
the Sender Address of your outgoing email to Email-Alias Address (or
vice versa) by selecting different value of the Email Address
field in the Personal Information Options.
Please note that you need to click
Save Changes button, then re-login
WebMail in order to make your changes of Name and Address in effect.
For details of applying Email Alias please refer to
here.