Xcode8.0 Beta 6 - unable to read from device

This is the error when the symbols are missing. Usually you get this error when your device has higher version than the Xcode such as iOS 10 vs Xcode 7.3 In this case Xcode 8 beta 6 failed to copy iOS 10 beta 6 symbols from the device.

1. Open Devices in Xcode
2. Select your device. It should have an unexpected error message
3. Delete "~/Library/Developer/Xcode/iOS DeviceSupport" directory
4. Unplug your device
5. Restart your device
6. Plug back your device
7. Xcode should start copying the symbol files immediately

I got it to work. Try restarting your device.

If not, delete the contents of /Users/yourusername/Library/Developer/Xcode/iOS DeviceSupport, plug it into Xcode again and let it process symbol files.