This message was posted on behalf of Intel Corporation
I would like to know if you were following the instructions in: http://www.emutexlabs.com/ubilinux/29-ubilinux/218-ubilinux-installation-instructions-for-intel-edison. If you want to continue using Ubilinux or recover it for using this image, I suggest you to contact http://www.emutexlabs.com/forum/index for more instructions because they are the owners of this image.
In order to recover the functionality of the board with Yocto, you can run the flashall script (not working for you) or the Phone Flash Tool Lite:
Are you using the breakout board or the Arduino expansion board? It could be also a problem in the power provided from the USB port of the PC.
Could you try to run these methods in another computer?