Explanation One of the possible causes of the error message "No Source Found" is that the projector is not receiving any signal from the connected device, such as a laptop1. This could be due to an incorrect input source selected on the projector or an improper display setting on the laptop. Therefore, the first actions that the technician should take are to verify the projector settings and make sure the correct input is selected, and to check the laptop display settings and set them to extend/duplicate23.