I am getting "Closed Loopback Connection" message and DR is not working


Note: "Closed Loopback Connection" is not an error. It simply means that the connection was closed, and this may be either expected or not.


Possible causes:

  • Corona is not activated on the render nodes
  • Problem with Autodesk Backburner
  • Using special (national) characters in object names, camera name, paths, asset names, etc
  • Problem with Corona installation on the node PC - e.g. there are doubled DLLs in 3ds Max folder, or some files are missing, and because of that 3ds Max or Corona cannot be started


Possible solutions:


  • On all render nodes: install Corona and open 3ds Max. Start render and activate licenses
    See: Activating License
  • On all render nodes: make sure you are able to perform a successful local Backburner rendering without any errors
  • Do not use national characters in 3ds Max, paths, or file names