Having read your situation I am more convinced that the arduino/ESP IDE programming software is up the duff. I am not prepared to throw more sacrificial boards to the broken ESP programming software. I sent another post of a similar nature viewtopic.php?f=26&t=3932&start=5#p31588 thinking I was stepping out on a limb but all my working boards that have gone duff are attributable to the new ESP programming tool which replaced the very working but supposedly "broken" ESPTool.exe. I can't believe that they have all gone through the essentially identical number of flash cycles ... one board has spent most of its life in development and another has recently been drawn from service to be reprogrammed, yet both have failed in the same manner. I have a pcb with provision for a stepper motor driver board for each of the ESP boards which are identical and use a plugin FTDI232 usb adapter for serial comms/flashing. I have been using these for 4 months with no problem and have even purchased a new FTDI because of the problems so I am convinced it is nothing to do with anything else but the IDE and ESP tools.
Having read your situation I am more convinced that the arduino/ESP IDE programming software is up the duff. I am not prepared to throw more sacrificial boards to the broken ESP programming software. I sent another post of a similar nature viewtopic.php?f=26&t=3932&start=5#p31588 thinking I was stepping out on a limb but all my working boards that have gone duff are attributable to the new ESP programming tool which replaced the very working but supposedly "broken" ESPTool.exe. I can't believe that they have all gone through the essentially identical number of flash cycles ... one board has spent most of its life in development and another has recently been drawn from service to be reprogrammed, yet both have failed in the same manner. I have a pcb with provision for a stepper motor driver board for each of the ESP boards which are identical and use a plugin FTDI232 usb adapter for serial comms/flashing. I have been using these for 4 months with no problem and have even purchased a new FTDI because of the problems so I am convinced it is nothing to do with anything else but the IDE and ESP tools.