Build app with Xcode 4 - it always show some error about PNG image

Question

When I build my app with Xcode 4 it always show this error message:

CopyPNGFile /Users/michaelchen/Library/Developer/Xcode/DerivedData/iMusicBox-boeawugacmha         


        

Answer 1

I got the same error. Turned out my pngs where actually jpeg. XCode showed them properly but an iOS device didn't. Solved it by saving the jpg as png.