You can change your email password in the Control Panel as the Domain Administrator or as an Email User.

1. Log in to the Control Panel as Domain Administrator or Email User (how?)
2. (bypass this step if you logged in as an Email User) Click on the 'Mail' icon in the 'Services' section (if you can't see the 'Mail' icon or 'Services' section, click on the 'Home' link in the top left hand corner of your screen)
3. (bypass this step if you logged in as an Email User) Click on the email address that you wish to change the password for
4. Click on the 'Preferences' icon in the 'Tools' section
5. Type in your new password (twice) and click on the 'OK' button.