It sounds like you may have a corrupted upload. Can you write 2.7.4 with the USB-Serial?
esptool.py -b 1500000 -p COM4 write_flash 0x000000 firmware.bin
We would reccomend a full erase first.
esptool.py -b 1500000 -p COM4 erase_flash
Substitute COM4 with your COM port
Yes, it does indeed sound like a corrupted unit. 2.7.4 has been totally stable on all the units that's it;s been testing on. What ESP WiFi device are you using? Is it the Adafruit Huzzah with the standard power supply?
Doing a full erase before uploading as Chris suggested is good idea.
Daniel Near
I've been trying for months to get the WIFI working on my EVSE. It had an old firmware originally. I think one of the 1.0 versions. Despite not having most of the newer features, it seemed to work good the year before. . I updated it to 2.5.2 several months ago when that was the latest version. It wouldn't see any WIFI networks once I did that. I rewrote the firmware thru USB-serial and it still wouldn't see any network. There 10-15 WIFI AP's in range. I tried 2.7.4 today, which it seemed to take (I got OK and now it shows that version on the System tab) and now not only do I still not see any networks, but the unit seems to reboot often. I tried downgrading to 2.7.2 but it won't stay online long enough to take the firmware.
Is this typical for the recent WIFI versions or do I maybe have a defective unit?