Mailbox passwords can be changed from the following link.
Alternatively if you have forgotten the current password, you can change it using the following steps:
- Navigate to Mail Info > Mail Manager.
- Select the domain you wish to create a mailbox for.
- Select the Edit Mailbox icon next to the mailbox you wish to change the password for.
- Within the Mailbox section, input the new password.
- Press Submit at the bottom of the page.