Active Directory Resync schedule does not remove unmanaged computers deleted from AD.
8.x.
ITMS 8.1 RU4 and later, by default computers are deleted 7 days after removal from AD.
When ‘Delete’ action is enabled, we check which affected resources have been imported by AD Import rules and only perform deletion to those which are older than the timespan defined by days in this setting: ADResyncDeleteResourcesThresholdDays. Computers are deleted immediately if this setting is set to 0. The default is 7 days.
To delete computers immediately after resync please do the following:
The last step is to run the AD Sync schedule in the UI or "NS.Directory Resync Update Schedule Item" scheduled task (NOTE: Shared Schedules will not show up here) on the SMP Server.
If systems are still not deleting, we may need to run the SQL in KB: 151975