Thank you for your email.

SPAMfighter does not work by blocking email addresses or domain names.
Because the spammers change email addresses on a regular basis, this would not be an effective way of stopping spam.

Each time an email is received by one of our many users, they decide if it is spam or not. If enough users think it is spam, and block the email, it will be filtered for all our users. Sometimes regular newsletters get blocked and that is often because it is to hard to unsubscribe or they did not know why they received in the first place. In this case you can "unblock" these newsletters, which will allow them to, from that point on, be sent to your inbox.

However, you have the possibility to block domains yourself through SPAMfighter by "More" > Blacklist > Domain

You can always get a overview of your blocked domains by going here :
"More" > Options > Blacklist & Whitelist > Blacklist domain > Open

But remember, this function is only applicable on your machine, and therefore does not block domains or addresses for any other users.