Networker Management Console, Media 'used' column

Hello,

The 'used' column for the Disk volumes entry in the Media window of Networker Management Console (v. 7.6.4)  shows a value 4863 GB for the Full.001 volume. The column '% used' shows 0%. When I right click the volume and ask for Show savesets, it replies with 'There are no savesets on this volume', which is consistent with the 0% used.

The same applies for the Incr.001 volume.

Nevertheless, I encounter the 'waiting for more available space on Full.001 adv_file', during a full backup. I assume that Networker stores a lot of its own administration data on this volume. In the log file I can see that nsrim is regularly running, but I suspect that there is data on the volume that is hidden and takes a lot of space. So my questions are:

- how can I detect that there is hidden data

- what is the best strategy to avoid the 'waiting for more available space' error

Thanks

Peter