Ionic serve point to cannot /get

Hi everybody,

Where I do ionic serve on my ionic project folder, http://localhost:8100/ return Cannot GET /.
Can be caused by a javascript error in my app?
What should I check?

If i go into the www folder I have no javascript errors.

Please help

I just realized ionic serve cannot be executed in the www folder, only in the project folder.
Thread can be closed for me.