Basically my samsung n145 netbook wont power up unless its connected to the power supply and also i cant disconnect the power supply when fully charged as it cuts the laptop off straight away :( cheers

Hi Ashley,
It clearly indicates that the battery of your laptop has deteriorated and cannot hold enough charge to run the system without AC Adaptor/ external Power Supply Source. So, the battery is supposed to be replaced with a new one. You may have noticed that the battery would be empty when you start the netbook and it shows 100% (fully charged) in a very less time. This happens due to the faulty/ deteriorated battery, which has very less charge holding capacity and hence shows fully charged in no time. If so, I suggest that you buy a new genuine battery (not any replacement), as genuine battery would last longer and serve you best.
On the contrary, if the battery gets charged normally and takes about 50-60 minutes to show 100%, then you may get the netbook checked by any authorized professional for complete hardware (Battery/ AC Adaptor etc).

Hope it helps! Good Luck! Thanks for using Fixya!
CreativeTECH

Replace your battery to solve this trouble.

Get a battery from a FixYa.com advertiser or anywhere computer batteries are sold.

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