Acer B1 A71 If the mobile gives watermark error or orange state warning, then vbmeta patching is required to remove it. But usually these patch tools work only when the mobile has secure boot unlocked. DA Auth File temporarily modifies the boot chain at that time, due to which that warning disappears and the mobile starts running in safe mode. This solution is especially helpful for those who want to use custom ROM or GSI ROM..
When the Acer B1 A71 mobile does not respond to pressing the power button and there is no sign of charging, most people consider it completely dead. But an experienced technician knows that if the internal boot system is alive, then it can be revived with the help of the DA Auth File. The importance of this file is that it provides software like SP Flash Tool with permissions that are usually not possible due to the security of the mobile. When the mobile is based on MTK chip and is booting only from the test point in Brom Mode, then this DA file allows you to write partitions using this test mode safely. When the preloader of the mobile is corrupt or the device is suffering from hang on logo, then usually no recovery or fastboot works, here by loading the DA file we not only write firmware but also format the userdata and make the device like new.