I am a doctor (Consultant in Obstetrics and gynecology) from Egypt and practicing in Kuwait, who takes electronics and manual labour as a hobby in my spare time, I have a 3D printer, hobby CNC, and do some RC flying too
Welcome to the LPF, Khomouda. I saw your other thread on the engraver. It likely use a Nichi@ laser diode NUBM44 which you have most likely fried, but can be had fairly cheap On Ricker's website. I would also replace the driver since you changed a part on it and it can no longer be inferred to be good. Enjoy your stay here and hopefully you will gain some knowledge here as well.