faithie999

thanks!! the updated voodoops2 that you linked to did the trick, as did the usb injector in your bootpack.

i just updated my E6420 from yosemite to sierra release version 10.12. i booted into yosemite, downloaded the sierra installer from the app store, and ran the installer from the /Applications folder. the update appeared to proceed normally and i was able to boot to the Sierra desktop. however, the usb (2.0) ports don't work. i am using rehabman's latest voodoops2 kext, which avoids the KP during boot. however, the keyboard and trackpad didn't work when i first booted to sierra. the "unknown keyboard" dialog showed up, so i connected via screen sharing from another computer and set up the keyboard. now the keyboard doesn't work but the trackpad doesn't. perhaps the keyboard doesn't connect via USB so this observation may not be of any value in troubleshooting. since the prefs that i set in yosemite included screen sharing, i am able to access the sierra install and poke around. just don't have any idea where to start the troubleshooting. in system profiler, both USB 2.0 hubs show up (i presume one is the internal and the other is the external hub. under the internal hub, the webcam shows up as a device. under the other hub, no devices show up despite having a usb drive and usb mouse plugged in. thanks in advance.