Duplicate item in content tree, throws "Object not set to and instance of an object" error

Question

I'm working on a project where we're using TDS. In my environment, I have a duplicate folder item that showed up under the root of my site. It's not unheard of to have issues like this when working on a team using TDS. However, the item is broken. If I click on it, Sitecore shows a dialog showing a .Net Object not set to an instance of an object error. This happens if I try to interact with the item via a right or left click.

If I run a sync with Sitecore from Visual Studio, TDS doesn't see the item at all. Any thoughts as to how it goes there and how to remove it?

UPDATE: to clarify, the item was "duplicate" in name only, which is assumed, but since I was unable to interact with the item, I couldn't see it's ID. However, using Sitecore Rocks, I was able to interact with the item and confirm that it was a second folder with the same name (different ID), created by another dev. Using Rocks, I removed it and all seems good. However, if anyone has experienced this error on an item via Content Editor, I'd like to understand more about how this can happen.

Answer 1

This is happen due to TDS conflict, when more then on developer work on the same item or item referenced by more than one TDS projects, on that node some time we faces this issue, because the same item sync more than once so it show duplicate item error. Even Sitecore content tree not able to resolve which item need to use and that gives a .Net Object not set to and instance of an object error because that item not properly resolved.

you can interact for that item by sitecore rocks or by DBBrowser admin page. For intract with DBBrowser you have to navigate to DBBrowser admin page as below:

http://{hostname}/sitecore/admin/dbbrowser.aspx

Hope that your query has been reolved.