Hi,
I am trying to upload the program to my Arduino board and getting the following message "Programmer is not responding" and "not in sync resp=0x31"
Board: Arduino Nano, port COM5
Processor: ATmega328P
OS: Windows 10
I tried all the steps mentioned in the troubleshooting forum such as reset. Nothing is working.
You just need to read a few posts below. 
If your IDE offers a "Nano (old bootloader)" option in the boards selection, try that.
I think it's because of you didn't install Arduino IDE properly try installing as instructed if you still having issues try updating Arduino port drivers .
If you solved your problem please let us know at
We are eager to learn