I am using the network option to retrieve a maintenance package.  Refer to Requesting RECEIVE ORDER via the web , section: "To retrieve a maintenance package using the network option".
  My SMP/E Receive From Network (RFN) job fails with the following messages:

 GIM45201S ** 530 Authentication failed.                                                                                 
 GIM46200I    RECEIVE PROCESSING HAS FAILED BECAUSE THERE WAS AN FTP ERROR.
 GIM20501I    RECEIVE PROCESSING IS COMPLETE. THE HIGHEST RETURN CODE WAS 12.

Generally, an Authentication failure indicates an invalid value in one of the parameters of the SERVER block:
In the email that you receive upon completing the Maintenance Order, you can click on link of the "completed ORDER", to display the "Login Details" to include in the SERVER block.

For example:


One common oversight is to use a host, copied from an old RFN job.  In this case, the following value needs to be corrected to match the login details displayed: