This is what I had to do for openHAB 2 to get it to work.
Use this command:
sudo nano /etc/default/openhab2
Enter password if it asks for it.
Change this line:
EXTRA_JAVA_OPTS=""
to this:
EXTRA_JAVA_OPTS="-Duser.timezone=America/New_York"
Then press Crtl+X to close the file, then press Y for Yes to save the changes, and then press Enter to overwrite the existing file.
After that restart the openHAB service:
sudo systemctl restart openhab2
Or do a system reboot:
sudo reboot
I tried to include as much detail as possible, for those who are as new to this as I am, who might stumble across this post. Honestly, I hate command line based interfaces. But it is what it is…