Stop auto launch

I do not want RingCentral to launch on startup of my computer. I've removed the shortcut from my startup folder and it keeps reinstalling itself every couple of days. I want this to stop. I've look all through the setting of RC and looked at settings, apps, startup and it's not in there. So why does it keep doing this? Make it stop! I want to turn it on when I need it, and not be on when I don't need it.