Add an email address or entire domain to your Spam Assassin blacklist or whitelist.
1.) Log into www.yourdomain.com/cpanel,
2.) Click on the “Mail” icon (or Mail link),
3.) Click on “Spam Assassin,”
4.) Click on “Configure Spam Assassin (required to rewrite subjects),”
5.) Scroll down to the boxes labeled on the left, “whitelist_from,”
6.) Add either (a) a single email address you want to receive mail from firstname.lastname@example.org or (b) add an entire domain name so you’ll get mail from anyone at that domain name, e.g. *@schmo.com. Careful with (b), you don’t really want to let anyone with a Hotmail account into your whitelist as lots of spammers use popular email programs.
7.) Scroll to the bottom and click “Save.”