NullReferenceException when trying to add a mesh to NamMesh Graph

hello everyone!

i’m trying to use NavMesh Graph using my own mesh made in blender, but i’m having a problem.
when i try to add the mesh to the NavMesh Graph i get this error:

NullReferenceException: Object reference not set to an instance of an object
Pathfinding.AstarPathEditor.SerializeGraphs (Pathfinding.Serialization.SerializeSettings settings, System.UInt32& checksum) (at Assets/AstarPathfindingProject/Editor/AstarPathEditor.cs:1313)
Pathfinding.AstarPathEditor.SerializeGraphs (System.UInt32& checksum) (at Assets/AstarPathfindingProject/Editor/AstarPathEditor.cs:1304)
Pathfinding.AstarPathEditor.OnUndoRedoPerformed () (at Assets/AstarPathfindingProject/Editor/AstarPathEditor.cs:1256)
UnityEditor.Undo.Internal_CallUndoRedoPerformed () (at <e6e2fa0a47414cd2ac33237924761b45>:0)

i was following this documentation so here’s what i did so far:

  1. opened blender
  2. deleted everything in the hierarchy
  3. created a plane
  4. subdivided it two times then delete the inner four quads
  5. exported as .FBX
  6. import into unity
  7. add an empty GameObject and name it A*
  8. Reset Transform
  9. add “Pathfinder” to A*
  10. add new Graph “NavMesh Graph”
  11. add Plane Mesh from the .FBX file to NaveMesh as the source mesh (Got Error)
  12. reset the mesh to “none” rename the .FBX file to “Plane” manually
  13. re-add Plane Mesh (Got the same Error)


Please don’t start multiple identical threads.

Would you mind posting the lines at which it gets a NullReferenceException (AstarPathEditor.cs:1313). Different versions have different line numbers so that would help a lot.

I cannot replicate this in my version.

sorry i deleted the first one and reposted it as a Beginner question.

i couldn’t replicate it either after basically updating the API


here’s what i did if anyone is wondering

  1. deleted Astar 4.2.15 from the asset folder.
  2. downloaded older version 4.2, installed the package and “updated” the API to the older version
  3. deleted 4.2 from the asset folder
  4. installed 4.2.15 again and prompt me to update the API
1 Like