Help needed with running local server at start-up, Rasp Pi 3

Blynk Servers
,
3

Hi Key,
Thanks for the reply but it still doesn’t work- please see below for what Ive done

This starts the server correctly-
""pi@raspberrypi:~ $ cd Blynk
pi@raspberrypi:~/Blynk $ java -jar server-0.39.4-java8.jar -dataFolder /home/pi/Blynk

Blynk Server 0.39.5-SNAPSHOT successfully started.
All server output is stored in folder ‘/home/pi/Blynk/logs’ file.
“”
Then I’ve done this in crontab -e

@reboot java -jar /home/pi/Blynk/server-0.39.4-java8.jar -dataFolder /home/pi/Blynk &

And also -
""pi@raspberrypi:~/Blynk $ sudo nano /etc/rc.local

!/bin/sh -e
rc.local
java -jar /home/pi/Blynk/server-0.39.4-java8.jar -dataFolder /home/pi/Blynk &
exit 0""

Any suggestions on what Im doing wrong?