Hello Williboy,
Is your SSE a Steam version? Have you purchased the Ferry Pack from www.shipsim.com ?
If your answer is "yes" to both of the above questions, then it is the reason as to why you are getting this message.
Please let us know. You should also read this post:-
http://80.95.161.114/shipsim/forum/index.php/topic,24877.msg330477.html#msg330477
Regards
vin_sun