Error after Xcode upgrade: couldn't add 'com.apple.XcodeGenerated' tag

Question

warning: couldn't add 'com.apple.XcodeGenerated' tag to '/Users/user/Library/Developer/Xcode/DerivedData/MyApp-sakjfljdasklsasadfkj;/Build/Intermediates/MyApp.build': Error Domain=NSPOSIXErrorDomain Code=2 UserInfo=0x22ea133a "The operation couldn’t be completed. No such file or directory"

I upgrade xcode 3.2 to 4.1

This MyApp worked fine before Xcode upgrade to 4.1

Answer 1

Clean your build folder! (⌥⇧⌘K)

Answer 2

After running, a window is opend.

I clicked 허용 or 승인 (in English, maybe "permit").

After clicking "permit" key, it works fine with no error.