Quote Originally Posted by Ryuluce View Post
" avrdude -C[path]/avrdude.conf -v -v -v -v -patmega1280 -cstk500 -Pcom3 -b57600 -D -Uflash:w:[firmware .hex file]:i "
I see you found a solution, but if this is the exact command string you've been trying, I think that may be your problem. Now I don't use AVRdude or even flash my printer, I just use the arduino IDE when programming my chips, so I may be way off here. But the bolded section usually needs replaced with a legitimate file name, not a generic place holder.

Edit: Dangit, didn't see the OP date.