Many times technicians want to downgrade firmware on Acer Z500 mobile, especially when the new version is buggy or Google Play services are not working. But with the new bootloader, the old firmware does not install. DA Auth File acts as a bridge here, which allows installing the old version by temporarily bypassing secure boot. This task is a very careful process, and if the DA file is not correct, the mobile can be completely dead..
In Acer Z500 mobile, if userdata gets corrupted or mobile factory reset protection is enabled, then tools do not write to the partition which contains FRP or userdata data. DA Auth File comes as a bypass layer at this time, which gives permission to the tool to access the encrypted partition. In most cases, thanks to this file, we can use options like 'Format All + Download'.