I have several people that when they send me an e-mail it is rounted to Spam Floder. I have opened and mark them as "not Spam" but the next time the messages still go into spam floder
Keep marking them as not spam. It could take a long time and lots of markings to help train the filters. You can also call Comcast security and see if they can tweak the incoming messages from those senders.
Comcast Customer Security Assurance-------------------
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