# Why am I unable to edit the Input Field object's script?

When attempting to edit an Input Field object's script like so

I get the following error:

Unable to open C:/Program Files/Unity/Editor/Data/UnityExtensions/Unity/GUISystem/UnityEngine.UI.dll: Check external application preferences.

Why is Unity attempting to open a *.dll, here?

Input Field is a class that belongs to the UnityEngine.UI namespace. Unity is attempting to open a *.dll because you are telling it that you would like to edit a class that belongs to that *.dll file. We can see this from the documentation; InputField is listed under UnityEngine.UI.InputField.
• @user89, I would rather not, as it goes outside of the scope of the question you ask, and would detract from the question for future users. If you do not know how to inherit, feel free to ask as an additional question, but beaware that it is a fairly simple concept to look up, and would be prone to judgement for lack of research. In simple terms, make a class with : InputField, just like how you would for a script that inherits from MonoBehaviour. I'm also confused as to why you accepted this answer; you said the other was more helpful. As such, you should accept that answer, instead. – Gnemlock May 31 '17 at 3:11