avrdude: verification error, first mismatch at byte 0x0000

Hello all, I have two Nano Arduino. The first one is brand new trying to upload the basic sketch example(blink.ino) and it working. Lucky, i have the second one it was been uploads at no problem at all however, till now and it has stopped accepting uploads, returning the following message:

"avrdude: verification error, first mismatch at byte 0x0000 0xff != 0x0c
avrdude: verification error; content mismatch"

the Nano keep blinking the "L" light in every about 1 seconds or 1000 miliseconds.

This message is received for all code uploads, simple (Blank.ino) to complex.
Different USB ports have been tried without success
Different USB cables have been tried without success
shutdown the computer and power on without success

I have no idea what wrong with the second Nano Arduino. Do you have any idea to solve it ?