running macOS Big Sur Beta 6 on iMac 2017 and/or Mac mini 2014. installed Xcode 12 beta 6 and Apple Configurator 2.13 beta 4. when trying to restore the operating system (UniversalMac11.020A5364e_Restore.ipsw) onto the DTK I'm getting an error:
The OS cannot be restored on this device.
Failed to restore device in recovery mode, libusbrestore error:21 [com.apple.MobileDevice.MobileRestore – 0x15 (21)]
tried to restore countless times, it fails always with this error.
DTK is bricked (orange (SOS) blinking LED.
mikeboss
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