I have no idea why shrinking the 'available slots' worked before but i am pretty sure that you must upgrade if you cannot 'program' your library to not report less slots.

if 8 slots not needed now...you can "partition" and allocate 40 slots...

Yes, that was my first (good) idea. But unfortunately the partitioning mechanism isn't so smart.

I can only partition an entire tray, so the options are 60 slots / 45 slots / 30 slots and I'm

losing 10 slots for good.

As Bingo said, in the past the slot shrinking method has worked fine for years... why not now?

Confused...

The NetWorker sees all the physical slots published to it for licensing. The SL150 does support partitioning, so that is the best option you have for now. Else, you will have to purchase the licenses for the additional slots.

Licensing goes against physical slots value (which is read-only field and I suspect re-read each time daemon initiates).  Value used can be seen also from nsrjb -V. Available slots was never used for licensing by default. SL48 could also be partitioned according to manual so I would not be surprised to learn that was done in the past.

Hmm... no, I never dit it, and I'm the only one that manages the libraries. I swear.

Anyway, with the partitioning I can reduce the available slots to 42 (giving to system the maximum

of 3 reserved slots) but there is no difference... I'm out of license for 2 slots!

I think that it's time to get rid of Networker and go for a more flexible (and cheap, BTW) solution.

Thanks to all for the support.

You should check capacity license - something which customers have been migrating to for years now.