Ethernet port leds dont turn on - no access to internet

You could have a bad network cable, or a bad port in either the router or laptop. I would try a different cable and then different ports on the router. If that doesn't work then I would say you might have a bad port on the laptop. In rare instances a driver might cause an issue but you would see the lights come on when you boot the pc but shut off when Windows gets going.

Thanks for the quick reply! I have tried with different kinds of cables, routers and internet connections even. I haven't succeeded with any, unfortunately. I tried what you proposed, shut down and reboot but the lights do not come on, at all. Is it possible that there is something wrong with the port?

I just rebooted and only the yellow led flickered. Is that good?

I would check into the network driver. It could be that the driver you have installed for it isn't working correctly. Normally when the system first comes up and sees the networking device and then gets disabled it is because of a bad driver.

You might want to remove the driver in safe mode and then reboot to see if it comes up and works while it is installing the new driver.