Using "Autobuild" in VSCode I have previously built a firmware.elf file in .pio/build/mega2560 which flashes with the Octoprint Firmware Updater Plugin without error on my Pi with a RAMPS 1.4 EFB board mounted on a Mega 2560 Arduino.
Using the same environment it NOW builds a firmware.hex file which errors.(see log files below.
Same Marlin Configuration.h file on all occasions
What did you already try to solve it?
Tried removing serial cable, pressing reset and reconnecting but no cigar. Don't know what else to try! Excuse my ignorance.
Have you tried running in safe mode?
No because as I understand it this will disable plugins.