We are currently trying to get our CMDB up to date with licencing, and we have come across a problem where the totals in the Software Details tab are higher than those in the installations tab, resulting in our software showing as under licensed even when we have available licences.

For example, we have verified 118 installations of visio, and 194 licences purchased, however, the totals on the software details tab show 123 installations with 5 unlicensed.  But when we go to the installations tab, it only shows the 118 that we expect to see.

What could be causing these phantom installations to show in the details tab?