Hi @Carlos Alberto Rojas Astudillo ,
Please ensure that license server is use Domain mode for discovery scope. If you configure domain discovery scope, terminal servers, without any additional configuration, can automatically discover a license server in the same domain only if the license server is installed on a domain controller.
Terminal Services License Server Discovery
http://technet.microsoft.com/en-us/library/cc772071(v=ws.10).aspx
Troubleshooting TS Licensing Installation
http://technet.microsoft.com/en-us/library/cc771756(v=ws.10).aspx
Best Regards,