I’m not sure why people can’t find the free license key that’s readily available on VMWare’s website. Here’s where to look for it:
- Visit the site https://my.vmware.com/web/vmware/evalcenter?p=free-esxi5&lp=default
- Click “License & download” and login with your vmware user account or register yourself a new one.
- Under “License & Information” you will find the VMware vSphere Hypervisor 5 License key.
Here’s a link to the procedures for getting the free ESXi 6.0 license.