As long as you can sign in to your plan with your Yahoo! ID, you can't accidentally lock yourself out of your site. You will always be able to get to all of your files and directories by visiting your File Manager, and from the Password Manager you can change passwords or delete user accounts altogether.

To reach File Manager or Password Manager, head to the Manage or Index tabs of your Web Hosting Control Panel and click the corresponding link. You can also access each tool by clicking its name in the left column of the other's main page.