Laser cutter won't cut

This is a very broad question, but some possible reasons could be: - The material you selected cannot absorb the laser energy. CO2 lasers cannot cut metals, for instance, unless very high-powered lasers are used and with the help of oxygen. - The laser mirrors are not aligned properly and the laser energy is not, or fully exiting the aperture of the nozzle. - The CO2 laser tube is not working, or the tube has passed the working number of hours. - The CO2 laser tube power supply is not functioning properly. To test this, you will need a special multimeter probe. This multimeter probe would be able to probe high voltage on the high tension line: https://amzn.to/3SywRuK. Seek the assistance of an electrician that works with high voltage devices before trying to probe. The high-tension line is approximately 10,000 volts and is able to arc a good distance. - The controller is not triggering the CO2 laser power supply. Do you see the laser tube glowing when you are triggering the laser with the controller? Is there a test button on the laser tube power supply that you can use to test the laser?