So randomly today all my usbs became unresponsive on my Lenovo y460p. The left 2 do nothing, the right 2 supply power but do not transfer any data. I have two unknown devices in my device manager, and they randomly connect and disconnect, but always go back to unresponsive.
So far I have uninstalled all the usb devices and reinstalled, updated bios and chipset, I used the microsoft usb repair utility, and followed the infcache.1 guide.
This could cause all the problems you've described. With your computer OFF you can bend the pins on the broken USB so they are not touching each other or the metal sides of the port, and it *should* restore functionality to the other ports. The cheap solution is to hot glue the bad port to keep it from getting buggered up again.
Ok, so I:
-ran the motherboard diagnostic tool from there, said it passed.
-lenovo's y460p user guide had no information on usb troubleshooting (I followed the guide for thinkpad next)
-checked bios for usb functionality, it was enabled
Motherboard repair may be an option as well. I've had good luck with repair services I've found on ebay, just depends on the value of the laptop on whether or not it's worth fixing. If you search your model number and motherboard, your likely to find replacements or repair options.