Select install zip from sdcard in recovery to enter back point-toggle signature verification.

Please notice the change at the bottom of the screen. If it is Endbled, it is on; If it is disabled, it is closed.

These two files are backup programs, but they really don't need to boot. Can be renamed:

① use Ctrl+Alt+Del to call up the task manager → process → select Dell backup program → end the process.

② Go to the main program folder and change the extension of the executable file exe to the suffix ex (change it back if necessary).

③ Click Continue to confirm the modification.