It's also worth noting that the encapsulating folder must be a "Group" for the others within it to be converted as well. Just converting the main Project folder converted all subfolders. :)

I tried removing AppDelegateAdaptor and AppDelegate file but still seeing error.

This actually worked for me as some of the other answers did not. However when I’m getting the screenshot, the image on screen has been rotated slightly but the screenshot does not show this effect. Any idea of how to get the screenshot to show exactly how the image is placed on its parent view?