rite having a few issues with my sisters laptop.
it decided to cook the charger while it was plugged into the charge point, leaving the plastic melted into the hole. (over heated because the heat sink had a layer of dust about 3 inches thick an fan stoped working!)
ive had it open clean the crap out of the heat sinks, new fan an new power brick, plug it into the mains an no charge goin to the battery. tryed a new battery an the it powers up an works fine, any sugestions on what else is worng? im assuming its some kind of internal power supply failure?
cheers for any help
pingu

Sounds like it may be a dell laptop - the centre pin of the power is a data line and "talks" to the computer, there is a tiny ROM in the power supply which tells the laptop how much power it can provide, if this signal is not present then the laptop will work on mains or battery, but will not charge the battery.

Usually need another power supply.

The power "pins" are the outer and inner of the outside ring of the plug.

As diggingdeeper says, some manufacturers force you to buy genuine chargers rather than aftermarket replacements.

Does it power without the battery in? As if it got hot enough to melt the rubberised plastic insulating the DC jack, it may have got hot enough to melt the solder and lift it from the mainboard.

no wont run off just mains. there is now charge light lit on the laptop. it was already running off another charger(not a genuine one) its a hi grade laptop (ive never herd of them either!) cant get much info off google about them either, so may struggle to get bits for it. ive just re read my post, i mean its still not charging the new battery

deppends on price