From IceBB Wiki

To log in you need an account at the forum. When you are logged out there is a link called "Login to your account" on the userbar. Click on this link to get to the login form.

Login form

The login form contains some fields that you will have to fill out:

Username

The unique username you chose when registering.

Password

The password attached to your username. First chosen when registering and maybe changed later.

Remember my login information so I don't have to login every time

Check this checkbox to make the forum remember your login using cookies. You should not check this if you are on a shared/public computer.

Do not show me on the online users list

Check this to hide you from the online users list. Certain privileged users may be able to see your online status disregardless of this choice.

When finished click the login button to log in to your account.