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NNC-00405:

network failure
Cause: The network connection between the client program and the name server has failed, either because the server has shut down, or because the network path to the server has stopped working. This error is usually displayed underneath an error which describes the problem in more detail.
Action: Contact your name server administrator to make sure that the server being connected to is running and listening on the address used, and that there is network connectivity between the two end-points.