I keep Getting Error: Property line - everytime I upload and compile sketch

Hello
I Just installed 1.8.3 Arduino IDE and even when I run the Basic Blink sketch example I get this error:

Property line ' # See: Google Code Archive - Long-term storage for Google Code Project Hosting.' in file /opt/arduino-1.8.3/hardware/arduino/avr/boards.txt is invalid

Error compiling for board Arduino/Genuino Uno.

Now I dont know about (Genuino Uno) but I have a UNO Board for shore.
Even when I switch to my Mega2560 I get the same error.
I Just cant figure out why I'm getting this error.

Any suggestions would be much appreciated

Cheers!

Did you edit /opt/arduino-1.8.3/hardware/arduino/avr/boards.txt?