avrdude: stk500_getsync(): not in sync: resp=0x00 tried everything nothing works

Hey so I am new to arduino

I have the Arduino Duemilanove and every time I tried to upload commands on it I keep getting this message "avrdude: stk500_getsync(): not in sync: resp=0x00" I know that I am for sure using the right Com port and I tried every board I also tried a different USB cable and the bootloader seems fine

Please help Thank you