In the meantime, another customer reported the same issue via email. Based on the information provided in that ticket, it appears that, specifically in El Capitan:
- The system_profiler command we use to retrieve software returns data when run locally on the computer.
- The same system_profiler command does not return data when run remotely, which is how Lansweeper scans.
Lansweeper doesn't appear to be doing anything wrong, but it appears that El Capitan handles remote security differently, or perhaps contains a bug. We'll perform some tests on our own machines to see if we can work around the issue, but it will likely take at least a few days to complete testing and draw conclusions.