EDIT: SOLVED
My board isn't an Arduino Uno, but an Arduino Nano (something I obviously knew, still trying to guess what I was thinking about earlier in the day)
Hi everyone!
I'm having some trouble with my laptop and my Arduino One, I can't upload sketches to it since my Windows doesn't recognize it. Let's start describing everything.
My computer has Windows 10 x64 (W8.1 previously) as OS.
I have Arduino 1.6.7 (the last version) installed.
I have worked with this board before in an XP without any problem.
When I connect the board to my computer, the blue LED lights up and the yellow-green blinks for a few seconds. Then, only the blue LED remains.
Once I open Arduino and try to upload an examen sketch (having selected the COM3 port, the ONLY ONE that shows up when Arduino is connected), it shows the typical error message that follows:
avrdude: stk500_recv(): programmer is not responding
avrdude: stk500_getsync() attempt 1 of 10: not in sync: resp=0x2e
avrdude: stk500_recv(): programmer is not responding
avrdude: stk500_getsync() attempt 2 of 10: not in sync: resp=0x2e
avrdude: stk500_recv(): programmer is not responding
avrdude: stk500_getsync() attempt 3 of 10: not in sync: resp=0x2e
avrdude: stk500_recv(): programmer is not responding
avrdude: stk500_getsync() attempt 4 of 10: not in sync: resp=0x2e
avrdude: stk500_recv(): programmer is not responding
avrdude: stk500_getsync() attempt 5 of 10: not in sync: resp=0x2e
avrdude: stk500_recv(): programmer is not responding
avrdude: stk500_getsync() attempt 6 of 10: not in sync: resp=0x2e
avrdude: stk500_recv(): programmer is not responding
avrdude: stk500_getsync() attempt 7 of 10: not in sync: resp=0x2e
avrdude: stk500_recv(): programmer is not responding
avrdude: stk500_getsync() attempt 8 of 10: not in sync: resp=0x2e
avrdude: stk500_recv(): programmer is not responding
avrdude: stk500_getsync() attempt 9 of 10: not in sync: resp=0x2e
avrdude: stk500_recv(): programmer is not responding
avrdude: stk500_getsync() attempt 10 of 10: not in sync: resp=0x2e
Problema subiendo a la placa. Visita http://www.arduino.cc/en/Guide/Troubleshooting#upload para sugerencias.
As it's said in in the troubleshooting guide, I've tried uploading the drivers:
Firstly, I've noticed that in Device Manager it only appers USB Serial Port (COM3) when the board is connected, and with any of the 3 USB ports of the laptop. Let's remember that is the only port which appears in the IDE when the board is connected (nothing appears if it's not).
Finally, when I try to update the drivers, I am told by the computer that they are already updated; but relating to USB Serial Port and not mentioning Arduino (have a look at the attached image, please).
I'm afraid this has more to do with the COM ports of my laptop, but I have no clues about how to fix this up. 
I'll appreciate any help. Thank you in advance,
Eduardo
