Philips 55PUS9109/12

Hello , I have a Philips television 55PUS9109/12 (sw version 000.010.126.000 05-11-2016) and want to install Kodi on it.
After the download of version 15 (later versions are not compatible with the software, is the message on the screen after download of them) I get the message that my TV is blocked for installing from a unknown source.
Anyone a idea how to istall it on my TV ?