problem with sketch upload

avrdude: no programmer has been specified on the command line or the config file Specify a programmer using the -c option and try again

This program occurs when you use Arduino IDE 1.6.8 or older with Arduino AVR Boards 1.6.12 or 1.6.14, they are not compatible. There are two different solutions to fix the issue:

  • Update your Arduino IDE version to 1.6.9 or newer by downloading and installing the appropriate file from http://www.arduino.cc/en/Main/Software.
  • Downgrade your Arduino AVR Boards version to 1.6.11 or older(or 1.6.13) via Tools > Board > Boards Manager

I have fixed the cause of this issue so Arduino AVR Boards 1.6.15 and newer will be backwards compatible with all versions of the Arduino IDE(except 1.6.6 for an unrelated reason).