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

In my case I discovered my corrupted png wouldn't open in photoshop. I opened in preview, saved as psd, and then saved again from photoshop (save-as -> png -> not-interlaced). Compiles fine now in xcode 4.