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I  would like to get rid of some people/companies/etc who  post on my Faceook page. Most of these are not Facebook friends, and I have no  idea how they were able to start posting on my page.  Facebook Help  is useless. Can anyone  please help me understand  how to do this? And I would appreciate making your reply with step-by-step instructions, as  my understanding of the details of Facebook is somewhat limited.

Thanks

Mike