Total active time is not detected on Windows Vista or later operating systems.
Total active time is not detected on Windows Vista or later operating systems, yet other operating systems do not have this issue and the total active time is measured.
On Windows Vista and later the total active time of a process is always 0. The usage agent uses the EnumWindowStations() API, but it no longer works as the SYSTEM is running in a different session of the logged in user.
There is an enhancement logged under FNMS-30499 to investigate other solutions.