We manage approximately 1,500 systems through LANDesk. I just recently (this week) upgraded our environment to 9.6. I had hoped that this would resolve an issue that has persisted since my predecessor was managing our environment. Of our 1,500 or so systems, there are about 40 agents that return no inventory information and fail to deploy packages correctly. Full re-installs of the agent have been tried on multiple occasions and seem to have no effect. When attempting to manually run an inventory scan, many return the message "ID 15531 - Failed - The system cannot find the file specified". This is despite the inventory scanner .exe being present on the system. Other systems afflicted by this issue run an inventory scan in a few seconds but return no data. Most of our systems function fine so this seems to be something specific to this small minority. I realize that there are likely multiple issues that could be causing this but I'm hoping that someone can give me direction as to where to start looking.