I have it figured out. The key was the following: EVEN IF THE DTK PLAYS DEAD (NO FAN, NO POWER LED, NO BOOT CHIME, NO OUTPUT ON DISPLAY) IT SHOULD BE IN DFU MODE NOW. from @mikeboss post on https://developer.apple.com/forums/thread/661096?answerId=634483022#634483022. I thought I had trouble putting the DTK in DFU mode, since it had so sign of life. I was resetting the power cable until DTK would chime and LED would show. That was a mistake. After rereading some of the posts, I realized that DTK was in DFU mode with no chime/LED/fan. I followed the directions in the guide and was able to restore DTK.

I'm still unable to restore the DTK. I have the host running 20A5395g, with Xcode 12.2 beta 3, and Configurator 2.13.1. I'm following the instructions from the https://download.developer.apple.com/Documentation/Universal_App_Quick_Start_Program_Resources/Restoring_Developer_Transition_Kit.pdf. The restore process always ends with the same error after a few minutes: Failed to restore device in recovery mode, libusbrestore error:21 [com.apple.MobileDevice.MobileRestore – 0x15 (21)] Has anyone been able to solve this?

Has anyone got this figured out? If so, what is the solution?

I ran into a similar problem. When using KextManagerLoadKextWithURL API, no error is returned on MacOS 11. On prior versions of MacOS, kOSKextReturnSystemPolicy would be returned. I believe KextManagerLoadKextWithURL API is used by both kextload and kextutil. Is there a new, programmatic way to determine if loading of a kext succeeded? Any help would be greatly appreciated.