Here are the step to change your main account's username's password.
2. Click on the "Account" tab.
3. Click on the "Admins" link.
4. You'll see your username, to the right of it you'll see the "Change Password" link, click it.
5. Type in your current password.
6. Type in your new password, then retype in your new password again.
(Note: You can also have the system generate a password for you, if you do, write or copy the password to somewhere to your PC.)
7. Click Finish.
You've completed updating your main account's username's password.