Xcode 7 warning: The launch image does not have a valid extension

Question

Xcode 7 has warnings for my launch image set. It reads:

The launch image set \"LaunchImage\" references a file \"Default@2x.PNG\", but that file does not

Answer 1

Can't comment, yet found this helpful:

After renaming the image's extension name to lowercase the warning goes away (as explained in the accepted answer: .PNG -> .png)

If the warning doesn't go away, clean the project by going to Product -> Clean

(or just: Shift + CMD + K)