Can't upload sketch to arduino Uno board I'm trying to upload a simple sketch to my Uno board but get this error message: avrdude: stk500_recv(): programmer is not responding (full error message at the end).

I have other Uno boards who work fine so I guess it is something to do specifically with this board (which used to work) and not my system or cables (port,drivers,settings etc..).

I did a loop-back test (http://forum.arduino.cc/index.php?topic=73748.0) on  the board and it worked fine.

I read about possible solutions but nothing seems to solve this.
https://stackoverflow.com/questions/19765037/arduino-sketch-upload-issue-avrdude-stk500-recv-programmer-is-not-respondi

I also tried using an Arduino as an AVR ISP but it failed. (https://www.arduino.cc/en/Tutorial/ArduinoISP)

Any help will be appreciated, thanks in advance.

Full error message: 

    avrdude: Version 6.0.1, compiled on Apr 15 2015 at 19:59:58
     Copyright (c) 2000-2005 Brian Dean, http://www.bdmicro.com/
     Copyright (c) 2007-2009 Joerg Wunsch

     System wide configuration file is "C:\Program Files (x86)\Arduino\hardware\tools\avr/etc/avrdude.conf"

     Using Port                    : COM3
     Using Programmer              : arduino
     Overriding Baud Rate          : 115200
    avrdude: stk500_recv(): programmer is not responding
    avrdude: stk500_getsync() attempt 1 of 10: not in sync: resp=0xd3
    avrdude: stk500_recv(): programmer is not responding
    avrdude: stk500_getsync() attempt 2 of 10: not in sync: resp=0xd3
    avrdude: stk500_recv(): programmer is not responding
    avrdude: stk500_getsync() attempt 3 of 10: not in sync: resp=0xd3
    avrdude: stk500_recv(): programmer is not responding
    avrdude: stk500_getsync() attempt 4 of 10: not in sync: resp=0xd3
    avrdude: stk500_recv(): programmer is not responding
    avrdude: stk500_getsync() attempt 5 of 10: not in sync: resp=0xd3
    avrdude: stk500_recv(): programmer is not responding
    avrdude: stk500_getsync() attempt 6 of 10: not in sync: resp=0xd3
    avrdude: stk500_recv(): programmer is not responding
    avrdude: stk500_getsync() attempt 7 of 10: not in sync: resp=0xd3
    avrdude: stk500_recv(): programmer is not responding
    avrdude: stk500_getsync() attempt 8 of 10: not in sync: resp=0xd3
    avrdude: stk500_recv(): programmer is not responding
    avrdude: stk500_getsync() attempt 9 of 10: not in sync: resp=0xd3
    avrdude: stk500_recv(): programmer is not responding
    avrdude: stk500_getsync() attempt 10 of 10: not in sync: resp=0xd3

    avrdude done.  Thank you.

    Problem uploading to board.  See http://www.arduino.cc/en/Guide/Troubleshooting#upload for suggestions.
In Arduino IDE check that


correct port number is selected in Tools -> Port 
correct programmer is selected in Tools -> Programmer (should be AVRISP mkII if you upload the code via USB cable)
correct board is selected in Tools -> Board (Arduino/Genuino Uno)


If above doesn't help, install the latest version of Arduino IDE.