Xcode: Could not locate device support files

I had a similar problem because the app store version was missing iOS 10.1 support in Xcode 8 and they haven't rolled an update yet. This caused the "Xcode: Could not locate device support files" problem. You can download the latest update https://developer.apple.com/download/ and it is more current and supports iOS 10.1 (14B72c).

Actually, there is a way. You just need to copy DeviceSupport folder for iOS 7.1 from Older Xcode to the new one. It's located in:

/Applications/Xcode.app/Contents/Developer/Platforms/iPhoneOS.platform/DeviceSupport/7.1

If you don't have the 7.1 files anymore, you can download a previous version of XCode on https://developer.apple.com/download/more/, extract it, and then copy these files to following path

/Applications/Xcode.app/Contents/Developer/Platforms/iPhoneOS.platform/DeviceSupport/

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