Windows Terminal Services::Licensing::Problem getting license across sites
Enterprise Terminal Services License Servers cannot be discovered outside it's AD site.
Hard-Coding Preferred License Servers
Regardless of which of these four situations a Terminal Server is in, you always have the option of manually specifying a license server or servers that each Terminal Server should get licenses from. You can manually configure any Terminal Server to get licenses from any license server—there’s no need to stay within domain, subnet, location, or site boundaries.
You can configure a Terminal Server to use a specific license server via the Terminal Server’s registry. Be careful though, because this registry edit is not like most others. In this case, rather than specifying a new registry value and then entering data, you have to create a new registry key (or “folder”). To do this, browse to the following registry location:
Add a new key called “LicenseServers.” Underneath the new LicenseServers key, create another key with the NetBIOS name of the license server that you want this Terminal Server to use. You don’t need to add any values or data under this new key.
Add multiple keys for multiple servers if you wish, although the Terminal Server will only communicate with one license server at a time. Once you’re done, reboot the server for it to take affect.
As you’ll see, this manual process is needed in situations where the Terminal Servers cannot automatically “discover” the license servers. It’s also useful if you want to override the default license server that a Terminal Server discovers.