DELL projector s300wi

If you've forgotten the password for your Dell S300Wi projector, a hard reset might be the solution. Turn off the projector, disconnect the power cable, press and hold the power button for 15-20 seconds, reconnect the power cable, and turn it on. 
Here's a more detailed explanation:
Turn off the projector: Ensure the projector is completely turned off.
Disconnect the power cable: Unplug the power cable from the projector.
Press and hold the power button: Press and hold the power button for 15 to 20 seconds to drain any residual power.
Reconnect the power cable: Plug the power cable back into the projector.
Turn on the projector: Turn the projector on, and it should be ready for use without the password.

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Iremove the cabel afrer i turned off  the projector and i press in the power 20 seconds

and the password still

Hello, after a month of arduous efforts and attempts without success, I tried the easy method and succeeded.
I connected it to a LAN, logged in with the password: admin, went to the display's control panel, and performed a factory reset, as shown in the screenshot. It works without a password by default.