Thanks for your help!
Yes I have the error stk500_recv(): programmer is not responding like a lot of people ! But it's strange that the Reset button doesn't make LED blinking.
Nothing connected to the board.
I've already success to upload sketchs with the board, sometimes working, sometimes not, with the same manipulation.
I should receive an other UNO board this week (I gonna try to change the ATmega328…)