Please note that when you enable the FrontPage extensions for a given addon domain name, then the only user who can access it is your main, CPanel one. You can easily add another one via the FrontPage Site Administration page for that addon domain, at
Please replace YOURDOMAIN.COM with your domain name. Follow the "Manage users" link to add a user to that FrontPage web.
If you add that new user as an Administrator then you will be able to log in to the Site Administration page with it.
Please do not hesitate to contact us - either via email, or via our support system at http://solid-hosting.net/clients - if you need further assistance.