For simple sign-in to just check emails and the basics: EASY sign-in click here
For additional features in your mailbox, you can ADVANCED sign-in here.(Note: on that page, you will have the option to use Horde, RoundCube or SquirrelMail, in addition to creating forwards, auto responders, etc. If you don’t know what any of that is, then you just use easy sign in and don’t worry about the Advanced.)
The mailboxes that have been set up are:
You have received the set-up passwords by separate email.
Here is the information you would need to set up these mailboxes in your iphone, ipad or other locations.