To reproduce: Follow the install instructions here: https://microsoft.github.io/AirSim/Unity/
Play the SimModeSelector scene.
Click the Car Mode or Drone Mode button.
Error message appears:
Problem in starting AirSim server!!! Please check logs for more information
The editor then quits.
Editor log shows:
UnityEngine.UnhandledExceptionHandler:<RegisterUECatcher>m__0(Object, UnhandledExceptionEventArgs) (at C:\buildslave\unity\build\Runtime\Export\Scripting\UnhandledExceptionHandler.bindings.cs:46)
(Filename: Assets/AirSimAssets/Scripts/Vehicles/VehicleCompanion.cs Line: 139)
Tested in Unity 2018.2.15f1 and 2019.1.0f2 on Windows 10.