How to change the jack with new one??

Hi there, it's Jack at Dyson.

If you've tried to repair your DC18 yourself without success, we would usually recommend contacting us directly for some further advice. If needed, we should be able to arrange for a chargeable repair of your machine by a Dyson engineer.

If you're interested in finding out more about your options, you're welcome to call the Dyson Customer Helpline on 0800 298 0298 (UK), 1-866-693-9766 (US), 1-877-397-6622 (CA) or 1800 239 766 (AU).

Assuming that the AC/DC Power Adapter is not faulty no LED lighting up at all and no image at all on the screen might mean a power management fault on the motherboard.
First try removing the battery underneath the netbook. Then connect the netbook to the power cable without the battery installed. If the netbook powers up without a battery installed then the battery is probably faulty most likely with completely depleted and unchargeable power cells. if so you will almost certainly need a new battery and some little known guidance on the correct management of a netbook or notebook battery (see below). Dead batteries tend to generate a more than normal amount of heat.
If the AC/DC adapter is not faulty and using the netbook without a battery does not help then check the DC power jack where the power cable connects to the netbook to see if the jack is loose or detached from its original solder point on the motherboard.
If the none of the above are the cause of the problem then the motherboard probably has a power track or capacitor fault which might be repairable (as would a loose DC jack) but these types of fault even if successfully repaired can easily come back and the cost of repair might be high compared to the value of the netbook and not worth it since a brand new state of the art netbook with a full warranty would not be very expensive.
Many users take an incorrect approach to netbook/notebook/laptop battery management. These batteries are rechargeable and are only supposed to be connected to the power cable when their cells are low or depleted. Once the cells are fully charged the power cable should either be disconnected and the computer used on battery power alone or the battery should be removed and kept for when battery powered use of the computer is next needed.
Once a fully charged battery is removed the computer can be used directly connected to the electricity without the battery installed.
A disconnected battery needs to be reinstalled and recharged from time to time if it is stored for long periods of time, because the charge in its power cells very slowly dissipates even if is disconnected from the computer.

I recommend to him not to do it because him lapto it is possible to put in shortly and is not going to ignite

If you have already changed the charger, and tried running it without the battery, it sounds like you have a Mother Board failure. You should contact Acer and have it replaced.

Hi:
The power jacks can be bought on line for less than $10, but the fun part is the repair. The laptop must be dis assembled to get at the power jack, and when you do get to it, it takes a deft hand and soldering skills to swap one out successfully.
I have done a few and am personally only about 50% successful. There are electronics shops that swap out the power jacks for about $150, and guarrantee their work.

this might help you out.... Magicjack install problem Google Search

Try a new power adapter before you try the other expensive tests and repairs. The adapters are notorium about failing after being used continuously . If you can check the outgoing voltage at the tip where it fits into the DC jack on the laptop would be good. Match the output to the rated voltage needed to peoperly power the laptop.

Call Philips, get replaced - this is a common problem across all mp3 manufacturers. You can look at the YouTube video on repairing mp3 player headphone jacks, but i doubt it will work without causing more problems with your mp3 player.

take it back to where u bought it and ask them

You DO NOT need to replace the motherboard. Laptop jack can be replaced. This place can do it for you, you ship your laptop to them, they replace your jack, then send it back. It costs $99. A lot cheaper than a new motherboard! http://www.800tech.com/ And so you know, I am not affiliated with them in any way.