1.To prevent the spread of virus in the firmware, which can cause harm to the ANTMINER S19 collection, the placing operate of “Protected Boot” has been switched on and also the “Root Authority” operate is disabled. If you haven't acquired your refund still, be sure to Check out your Paypal https://jeffreythkcx.blogchaat.com/34638339/details-fiction-and-bitmain-antminer-s21-pro