Machines are automatically deactivated after they have been inactive for 30 days. Consequently, most sites never need to explicitly deactivate licenses.
If you are seeing messages that you are over your license count, please request a license report from support@tripletriangle.com. We can work with you to help deactivate machines that should not have the software, or to purchase more licenses.
If you are doing a one-time machine replacement, please contact us and we will reset your licenses.