Why is my laptop not recognizing a connected external monitor?

1. Check all connecting cables to ensure all are securely plugged in.
2. Ensure that external monitor is powered on and the brightness is adjusted to an optimal level.
3. Reattempt connection.
4. Check your laptop’s ports to ensure that the monitor cable type is compatible with the laptop’s ports.
5. Check device settings on the laptop to make sure that it is set up to recognize an external monitor.
6. Try to connect to a different monitor, if available, to diagnose the issue further.
7. Check your laptop’s display settings in the device's start-up menu.