I removed all plugins from Ressources/plugins, but unfortunately it didn't change anything. Furthermore, I found out that SID KO4D (ULLI, 10L) crashes X-Plane, too. KO3D works fine. By the way, there has been one oddness since 1.4.2: When I start X-Plane or open the CRJ, most of the time the plugin for the CRJ is loaded but disabled. On the other hand, the crashes occur regardless of whether the plugin is disabled at the beginning or not. I guess the reason for the last line in the Log.txt is that X-Plane was already listening on port 18387 when I enabled the plugin by hand. Log.txt