I have changed some URLs in my site then to prevent Webmaster Tools duplicate error I redirected (301) old URLs to new URLs also I tried to remove old URLs in "Optimization > Remove URLs" section of Webmaster Tools and still I get "Duplicate title error".
I want to know is any problem in redirecting?
http://www.example.com/index.php is redirected to
P.S.: I used Fiddler to check 301 redirect and think it should be okay.