You can run activeCollab on your local network as long as it operates on one URL. For additional installations you will need to purchase additional licenses.
You will need to insert the URL you will use with your activeCollab setup. If it's localhost use localhost, if it's activecollab.lan use activecollab.lan etc.
is it possible to install activeCollab on an internal server? I have to tell you a domain name (when buying it) where I want to install the system.
But if I don't want to install it on a web server, only on my internal company server: Does that work?