laptop not recognising its plugged in

Hi

My Inspiron 15 is not recognising that it is plugged in at all. The green light is on on the adaptor and the chord is not damaged. The battery is fine, it charged perfectly when I put it into nother dell and works fine back in it's original Dell. The laptop is not recognising that the chord is plugged in at all.

Any idea what the problem is?

Thanks

Cyan