Looks like it means the mesh that was supposed to be used by Niagara is not in memory (not marked as “allow CPUAccess”). It happens in packaged project. The only useful information here is the " NiagaraDataInterfaceStaticMesh " part.
Maybe a little something in the documentation or improving the error output could help.
Or maybe automatically check this parameter when mesh is called from a blueprint / Niagara system ? It can be very complicated to activate it in every mesh that will need it in a project and I suppose it’s not a good idea to enable it for any mesh.
Have a nice day / evening
Edit : I also had to set the mesh at runtime so I’m sure it’s loaded.