All you have to do is know where VirtualBox is installed, change the path to it below, then also change the name of the virtual machine (VM) you want to autostart below.  Here, upon boot up, I have one of my local development servers auto start “vm1”, which is a Ubuntu web server with a few Symfony projects.

cd "C:\Program Files\Oracle\VirtualBox"
vboxmanage startvm "vm1"

Fast, easy and reliable so if your server restarts, you don’t have to worry about your server staying offline.