The -300018 specifically, indicates that the the planning run is set as if the process is already running…  

Planning is exclusive and only one process can run at a time.


If the Background Task status messages indicate that planning failed because it is already running.....


Steps to RESET the Status:

  • Login to CSI
  • Open APS Sites and Alternative Management Form
  • Select the Actions Menu
  • Select Clear Planner Status
  • Run the APS Planning process.


For any other error code refer to the help (Troubleshooting APS) which lists other failure statuses and resolution actions.