Here's how to flash when Flash Tool Lite does not work
I've been having a real challenge getting any of my three Edisons working properly. At first, in order to follow the directions properly, I downloaded all of the drivers and installers to my Windows 7 partition. I installed everything, and connected the Edison as directed with the mini-breakout board. Connected the board with both USB cables and a 12v, 2 amp power connection to J1. Started the Flash Tool Lite, loaded the latest image, and plugged in both USB cables. And... nothing! The board was not detected by Windows. Never to fear, I have another new Edison and breakout board. Connected that Edison in the same way as the first, and... nothing! The second board was not detected by Windows. Same with the third.
Never to fear, I have a fresh Ubuntu install that I did for this project. Same thing: downloaded and installed all of the tools, and... nothing! None of the 3 boards were detected by Phone Flash Tool Lite on Ubuntu. So I did some more digging. SparkFun has a tutorial on how to install a different OS on the Edison. That was no good because I'd rather have the Edison as-is. HOWEVER... in that article, there was a clue. If you're fast enough, you can interrupt the Edison boot process by using a communications tool on /dev/ttyUSB0 and connecting right as the Edison starts. And then, when you interrupt the boot process, you can use this command:
Once you run that command, you can then use the flashall.sh script (which is found in the Zip archive that is the firmware image), and presto! The image is flashed!