Power Surge on Hub Port???

Archived from groups: microsoft.public.windowsxp.help_and_support (More info?)

i keep getting a message that says "a usb has exceeded the power limits of
its hub port. for assistance in solving this porblem, click this message."
When i click it it takes to a listing of all my usb ports and there is on
listed as an unknown usb device with a yellow exclamation. the thing is that
there arent any usb devices connected. what can be the problem?