I bought a computer 2 months ago and I had a problem with the charger recently, now that I have a new charger i tried to open it but it says: The hardware on this computer has been deactivated.Can somebody tell me please how to get the code to unlock my machine?

are there any lights on the computer when you plug your charger in? the most common cause if there are no lights is that the charger is faulty, if you have a multimeter you can test it, otherwise I'd take it to an IT professional to get it looked at

try to boost the battery with external charger or find another battery and try to see if will solve the problem

Sounds like the battery itself--even though the computer is new-those type of batteries have a limited shelf life and start to degrade from day 1...Is it still under warranty?

Turn everything off. Take off the battery. Connect the ac adapter and turn on your computer. If it works with the ac adapter connected and your battery off then you have a defective battery.

If it does not work then it's either your ac adapter or your dc jack inside your computer. Try a different ac adapter at the store you bought the battery and you'll know if your adapter is bad. If it works with another adapter then exchange the adapter again (I know, I know, I've been there). If it does not work with another adapter then you're back to the dc jack but at least you'll know for sure.

Make sure that whoever is replacing the dc jack is good at soldering and replaces it not just solders the same one back on. Don't forget the shield to the dc jack. Good luck!

I would take it back right away, when electronics break down in lees than 6 months it is not a good sign. Get the replacement or have it fixed under warranty.
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If you've only bought it 2 months ago it will still be under warranty.

These things will happen. You are aware that these appliances have a 12 month warranty so return it to where you purchased it from.

Time for a new fan, also you should try and get as much air flow underneath as possible.. have you tried those laptop coolers that the laptop sits into.. Clean any opening out of dust too.

Try an Antec charger with an adjustable votage output. I tried a new battery, charger, BIOS udate, etc, etc, etc. After fighting it for about 2 months, I found the Antec at Best Buy. Took it home, plugged it in, slid the adjuster up till the "charge" light came on. Been working fine for about 6 months.

Hi!
If the unit was a Brand New purchased, and still 4 months old, its better to avail the "warranty" of the unit, to save you from any trouble. But if it is a second hand without any warranty, you can eithertake this risky step or submit it to a certified service center.
The risky step is to open your laptop, and check the "charger terminal" for loose contact, or solder detached terminals.