Changing a mailbox password does not affect the mail already stored in it. You'll just need to update the password wherever the account is set up, such as Outlook, your phone's mail app, or webmail, once you've made the change.
In cPanel
- Log in to cPanel and open the Email Accounts tool.
- Find the mailbox you want to update and click Manage next to it.
- Under Security, enter a new password, or click Generate for a strong one.
- Click Update Email Settings to save.
In DirectAdmin
- Log in to DirectAdmin and open Email Accounts.
- Click the email address you want to update.
- Enter a new password in the password field.
- Click Modify or Save to apply the change.
After changing a mailbox password, mail apps on your phone or desktop will keep failing to send or receive until you update the saved password in each one. Update webmail bookmarks or saved logins too if you use them.
If you've forgotten the mailbox password and can't log in to check it, this same process resets it, since you don't need the old password to set a new one from the control panel.