Duplicate Urls for many terms I don’t know why most of my parent terms have duplicate URLs:
One like this:

     taxonomy/term/1


And a second one like this:

     taxonomy/term/1/0


I have installed Global Redirect and Pathauto, and all urls in the first format are redirected to their alias. However urls in the second format are not. 
Now google is reporting a large list of duplicate title tags. How can I solve this?
There's a setting under the Global Redirect settings to Remove Trailing Zero Argument:



According to the description for this option:


  If enabled, any instance of "/0" will be trimmed from the right of the URL. This stops duplicate pages such as "taxonomy/term/1" and "taxonomy/term/1/0" where 0 is the default depth.


That should fix the problem you're having.