Where is your zip file located? I've had issues with the recovery sometimes not seeing the external SD card. Possible solutions in order of how much of a pain it is:1) This is somewhat hard to do, but try holding both the power switch and volume up, and hit the reset button. Keep holding both until the recovery screen comes up and hopefully it will start flashing.2) Pull the back off and remove the internal SD card, try again to flash off the external card using (1) above.3) Put the firmware on the internal SD card, put it back in, and flash again.You don't have to do all 3, just whichever one gets it to work.