Change your groups message posting name
Depending on how you post messages to your group, there are a couple of ways that Yahoo Groups may display your name to your fellow group members.
Posting via the web
By default, your Yahoo ID will display next to your group posts.
Use an alias in your group -- your alias will display in place of your Yahoo ID when you post.
Posting via email
By default, your name as it appears on outgoing email from your email account (your "From" or "Sending" name) will display next to your group posts. If you haven't set a sending name in your email account's preferences, your full email address will display on your groups posts, instead.
Changing your sending name
In Yahoo Mail, learn how to change your sending name. This changes your name as it appears on outgoing emails, and on groups posts you make via email.
If you use a non-Yahoo email provider, please consult their help or support website as the steps for changing your sending name vary.