From Gordon Rigg

Resurrecting a bad esp8266.

I had a board that seemed dead. At first it wouldn't flash. Then I found a blob of solder shorting near the chip. Then it flashed but wouldn't work. I had assumed the short had blown something. Phil Colbert said it might be possible to get it going by flashing it completely blank but it was quite a faff. I followed the instructions here:

http://www.pratikpanda.com/completely-format-erase-esp8266…/

Only using the flasher program we already have with the bank_1mb.bin file they link to.
Type the three addresses in three lines of the programmer and wait a long time for it to flash with nothing.
Then unplug and replug and flash as if its a new board.
Then my board came back to life.
If you have any esp boards that don't work, its worth a try.