Reply To: Webmaster Tools duplicate content.

It is not hurting your rankings, please do not worry. These things will come and go over time and it takes a very long time for tools to reflect the changes. It never made sense to me and I freaked-out for a long time trying to figure out why, or how to fix it, but in the end… search is smarter than web-tools lol. It will eventually go away with the canonical tag.