You can find a master who knows how to power, use a multimeter to measure your adapter, (that is, you plug the computer connected to the power supply on behalf of the charger's connecting cable) to the adapter 220v that end, and then use the multimeter DC gear to measure the output voltage, and whether the computer voltage required to adapt, (that is, the 220v that end plugged in, this side of the head plugged into the computer, do not plug in the computer, with the meter to measure the computer, and whether there is power). (That is, the 220v header plugged in, this side of the header plugged into the computer, do not plug the computer first, use the table to measure whether there is electricity).

Then there is the computer socket internal power conversion switch is bad. But this is unlikely.