I built my website four months ago and was using WordPress. I have my url set up as www.xxx.com/date/title of the post at first hand. After about three months, I change the url to be only www.xxx.com/title of the post.
And I get the the duplicated title tags in Google webmaster tools. I just know that it is the worst idea ever to change the post urls after seeing no more traffic from Google.
Please suggest me the best way to solve this problem.
Here is the screenshot of some duplicated urls. I have hundred of them.