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In trying to knock down the most common errors on our site, we've noticed we do have an issue with dupicate content; however, most of the duplicate content errors are due to our site being indexed with www.www and not just www. I am perplexed as to how this is happening.  Searching through IIS, I see nothing that would be causing this, and we have no hostname records setup that are www.www. Does anyone know of  any other things that may cause this and how we can go about remedying it?