Starting with ITMS 8.5, software without an uninstall string is not captured by Inventory. This is due to the requirement to have an uninstall string for valid installed software.
Installed Software data and the Add Remove Programs data will not capture software, omitting them from the results.
ITMS 8.x
Inventory Solution 8.x
Misconfigured software installers may omit the uninstall string in the registry under HKEY_LOCAL_MACHINE\SOFTWARE\WOW6432Node\Microsoft\Windows\CurrentVersion\Uninstall.
Installers can also be packaged to disallow users to uninstall them by removing registry components from the registry.
Use this method to inventory these installed applications. the following walk-through provides an example of how to do this: