Failed to open Script Editor - Despite installed all programs and changed prefer. to Monodevelop

As above, I was trying to open the script editor but nothing appears. Not even a single window appeared.
I installed .NET, Xamarin studio and such. what can I do now?
(I am trying to learn gaming using project Roll a ball, it seems easy on the tutorial)

Hi @FlaminghawkTH . Can you give some more details such as your Operating system and the version of Unity you are working in? Thanks.

-Paul