Windows 7 - Reset of USB port after probable power surge

Desktop Pc : Dell XPS 8300
Operating System: Win 7 Professional
Total 6 port, 2 External Port on the top of CPU, probably 4 on the back.

Problem: Usally my seagate external hard drive is attached to the top second port always. On a nice morning, 2 day back I got a message from the system tray (after system comes off from night sleep) that " USB mass storagedevice has exceeded the power limits of its hub port". After I close the window (in a hurry), I could not able to activate that port, but power is coming to the ext. device if attached but not recognised by the system. The port next to it, is working fine.
My dell phone support system could not solve the problem, now his engineer will make a visit, don't know what he will do.
Clue: One interesting thing i have found under universal serial bus controller, that one drive named "USB Mass storage device " always remains at present, however, if I attach the external device to left USB port, another "USB Mass storage device " drive is created and is removed when I detach it. But this is not the case for the faulty one.
Request: How can I reset my faulty port to come back active. please help,

Best Regards
Raj

Try this, shut down the PC, unplug the power cord for the power supply from the wall outlet. Now press the power on button on your case and hold it for a couple of seconds. The power Led should lite up briefly and then fad out. Now plug the power cord back in and power up normally. With a little luck the USB port will be working again. I've gotten that same message on my PC and the above procedure fixed it for me.

If you are curious as to why this works, see Use Hard Reset to Resolve Hardware and Software Issues HP Pavilion dv5000 Notebook PC series - HP Customer Care (United States - English) for very informative reading.

As far as USB ports go, they are overload protected. If a device tries to draw more than 500 MA in current the port will shut down. The only way to reset the fail safe circuit is to completely remove all power from it. PC power supplies have an Auxiliary +5v supply in them that is always on, even if the PC is powered down. The Aux supply is what is used to power the motherboards start up circuitry and may do other things as well. Unplugging the power supply and then pushing your case power button drains any residual power and drains the Aux +5V supply as well. With all power removed the USB ports reset themselves.

Great Reply!!!!!!! Very Informative, I will try and pass on to my DELL support staff.

Regards

@writhziden, nice post, good info.
@raj4seven, did you try it, did it work?

Thanks man!!!!! It worked, now am so so happy. Lots of wishes and a Happy New Year both of you