Asus p8z68 v pro

I have just bought a new pc
with config
Asus p8z68 v pro
i5 2500k
4gb * 2 ddr3 corsair
msi 6850 cyclone edition
cooler master elite 430 black

the problem with me is the front panel usb connections. when i got it assembled the person who did it by mistake connected the front panel usb to ieee port on the mobo     because of which my many devices burned off
     
now i have corrected it and connected to the usb only but the problem is that the its not working even now..
i have checked the voltage to see if the connections are rightly made and i am getting 5.2 on both the usb 2.0 on the front panel...
the back panel ports are working fine..
PLZZZZ Help...................