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After updating my devcie to iOS 9.3.1 Xocde giving "could not find developer disk image". I am using xcode 7.2. Please help.
You need to download Xcode v.7.3. to use > 9.3 iOS version. And to upgrade to Xcode v.7.3. your Mac OSX should be upgrade to 10.11.5 or greater at least.
来源：https://stackoverflow.com/questions/36354977/could-not-find-developer-disk-image-stack-overflow-xcode-7-2-ios-9-3-1