A whitelist/blacklist is a list of e-mail addresses or domain names from which our firewall will reject/allow messages that are received. Our firewall is intended to prevent most unsolicited e-mail messages (spam) from appearing in your inbox. Not all firewalls are perfect though. Cleverly crafted spam gets through, and a few desired messages are blocked which is why we made it possible for you to whitelist and blacklist specific email accounts and domain names.
Here is how you can do it:
First step is to log into your Customer Zone.
Once you are logged in, hold the cursor over "Services" found in the menu bar and click on "Spam Firewall"
On the new page, click on the "Login to Web Interface" next to the domain you wish to make changes to.
You should be redirected over to the Firewall's interface where you would see the whitelist and blacklist option in the left hand column.
Select the action you wish to complete and enter the entire domain you wish to whitelist or blacklist. Click on "Add" to complete the request.
If you do not have access to the customer zone you can use the "Forgot Password?" feature to reset the login details.