The answer to 'lighting installation not working' is that there are several common causes, including faulty wiring, a bad light fixture, or a problem with the electrical circuit. Symptoms may include the lights not turning on at all, flickering, or only working intermittently.
Some DIY solutions to try include checking the circuit breaker, inspecting the wiring connections, and replacing the light bulb. However, if the issue is with the electrical wiring or the light fixture itself, it's best to call in a professional electrician to diagnose and repair the problem safely.