I received the arduino nano I directly bought on arduino store. I also dl the arduino IDE. Everything was fine until I tried to upload a simple example (blink the builtin led) into the arduino... 
I chose the configuration : Arduino Nano ATmega328P on the right port COM but i got this error :
avrdude: stk500_recv(): programmer is not responding
avrdude: stk500_getsync() attempt 1 of 10: not in sync: resp=0x90
avrdude: stk500_recv(): programmer is not responding
avrdude: stk500_getsync() attempt 2 of 10: not in sync: resp=0x90
avrdude: stk500_recv(): programmer is not responding
avrdude: stk500_getsync() attempt 3 of 10: not in sync: resp=0x90
avrdude: stk500_recv(): programmer is not responding
avrdude: stk500_getsync() attempt 4 of 10: not in sync: resp=0x90
avrdude: stk500_recv(): programmer is not responding
avrdude: stk500_getsync() attempt 5 of 10: not in sync: resp=0x90
avrdude: stk500_recv(): programmer is not responding
avrdude: stk500_getsync() attempt 6 of 10: not in sync: resp=0x90
avrdude: stk500_recv(): programmer is not responding
avrdude: stk500_getsync() attempt 7 of 10: not in sync: resp=0x90
avrdude: stk500_recv(): programmer is not responding
avrdude: stk500_getsync() attempt 8 of 10: not in sync: resp=0x90
avrdude: stk500_recv(): programmer is not responding
avrdude: stk500_getsync() attempt 9 of 10: not in sync: resp=0x90
avrdude: stk500_recv(): programmer is not responding
avrdude: stk500_getsync() attempt 10 of 10: not in sync: resp=0x90
Problème de téléversement vers la carte.
Furthermore, I tried another configuration : Arduino / Genuino Uno and I re uploaded the example blink code and it worked fine ! whereas I am not using an Uno but a Nano...
In order to use correctly the I2C part, I need to use the correct configuration that is to say the nano one... Can you help me ?
(I have no old bootloader atmega328p in my config and my nano was bought on the official website arduino)
Thanks in advance !