无效的图像路径-在关键字“CFBundleIconFile”:Icon.png下引用的路径上没有找到图像

I got this error from Application Loader when uploading my app to App Store. My app was developed at the time of iOS 3.0, and still targets at iOS 4.3 and above. I recently updated the app to make it iOS7-compatible. But the Application Loader always returned this type of error to me. I searched the Internet and found that I am not alone. So I created this post and hopefully what I found out about the app icons can help other people.I got this error from Application Loader when u