can someone help me?

if anyone uses mozilla thunderbird here, how do you get 1 address to always go to your inbox?

it's actually currently this forum i'm having problems with

all the replies are going in my inbox, but if i get a private message or i am subscribed to a forum, it goes to my spam

i don't get it.. and it's driving me crazy

it's not just this site, another list i belong too i get all the messages in my inbox like the conversations, but any attachments from it go to my spam.

it's.... odd