Trade routes established to the wrong planet. Build B4B.
from
Stardock Forums
This is a really wierd bug on build Beta 4B. I built a freighter at star system A and sent it to the Yor's planet B to establish a trade route. But the route was established between my planet C and the Yor's planet B. Then I had planet D build a freighter and sent it to the same planet I sent the first freighter (Yor's planet
and that trade route became established between my planet C and the Yor's planet B (the same route as the first freighter).