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It is very difficult to tell you something if you don't tell us where to find your website. If you could post the url here in the following format: domain (dot) com then we could give you an accurate answer. My first guess is that you haven't set up a proper rel=canonical. In the eyes of a computer the following URL's are all different pages. www.domain.com domain.com www.domain.com/index.html domain.com/index.html www.domain.com?sessionid=1 etcetera... If you're not canonicalizing your pages or redirecting them properly then a computer such as a search engine will see it as different pages with exactly the same content. As i mentioned before, this is just a guess and i can't give a proper answer without knowing the URL of your website. Hope my answer will be useful to you.