Make sure you setup authorization for both the Netapp you are trying to backup 
and the device host that has the tape drive.  If you've attached the tape drive 
to the Netapp, then they are the same and one entry will cover it.  However, if 
you are using Remote NDMP on a media server and are backing up the data over 
the network via 3-way NDMP, you'll also need to setup auth for the media server 
itself.

Also, error code 99s are extremely generic for NDMP backups.  Even though it 
suggests checking set_ndmp_attr, that is not always the problem.

Get the bptm pid from the job detail, and then get on the media server used for 
the backup.  

grep <pid> /usr/openv/netbackup/logs/bptm/<log.date> | grep NDMP

The real problem should be evident from the output.  If your media server is 
windows, you'll have to adapt the path above accordingly.