The server cannot update the event record for the specified client node. The existing record indicates that the scheduled operation has already completed. This can happen when two or more client schedules are running for this node, or because the client has retried the operation after an error has occurred.
Server operation continues. The existing event record is not modified. No further processing is performed for this scheduled operation.
Contact the user for this client node, and make sure that only one client scheduler is running.