Your friend probably hasn't installed the Orbx Libraries - https://www.fullterrain.com/support
That was asked on the forum. He says that he has installed it. No one couldn't find the solution. That's why I am asking here. He was also told to ask from the Orbx forum. No answer yet. No one of us have met the same problem. I think that his English isn't good so perhaps he isn't able to solve the problem on international forums. The discussion on FSNordic goes in Finnish or Swedish (he speaks good). If I cannot find the solution here I think I go on the Orbx (though I am not a member there yet).
Pekka