It's one of three things:  bad adapter, bad DC jack or bad mainboard.  Try a new OEM adapter first (or visit a local shop that almost certainly has one you can try).  If that solves the problem, you're set.  If not, the DC jack is the next part to replace. One of those two usually solves the problem.  
Inspiron laptop (the model number on the label is worn out) picture attached When the charger is plugged in I get the error message to plug in a 65W charger (see pic).   I'm using the original charger.   Is this a sign of a bad charger?   The laptop still runs when plugged in.  I have not tried it on battery. I don't have another 65W to try. Suggestions? [IMAGE]
Inspiron - 65W charger