To change your email's current password please follow these steps:
Instructions for Simple Email Customers:
Login to your account and click Domain Manager.
In the Email New box beneath your domain click Edit Emails.
Click on the gear icon under Manage then click Edit Password.
Enter your new password then click Save.
Instructions for Hosted Email Customers:
Hosted customers can follow the above instructions, or change their email password in the Hosting Manager as detailed below:
Login to your account and click Hosting Manager.
Click the green button that reads Control Panel. This will open the Hosting OS in a new tab.
Under Sections click Email then Show Accounts.
Under Email Address & Password enter your new password in the boxes provided. When you are done click Save.