This feature only applicable to Splashtop Center v2.3.10.x [coming soon] and above.
If no new users are automatically imported to Splashtop Center via Active Directory Auto-Sync. Please check the following from both ends :
Active Directory server
(1) Check if there is indeed new users added to the AD Group or Organization Unit, from which you want to import.
(1) Check if the AD Auto-sync function is enabled
(2) Check if the settings of AD Auto-sync is correct
(3) Check if the settings of domain name and AD server are correct
(4) Check if AD Group or Organization Unit settings are correct
(5) Check if the users that aren't imported via Auto-Sync, aren't users that are deliberate left out from previous manual bulk import setup. Splashtop Center will treat those as users that IT admin doesn't want to import, thus will ignore/bypass in the Auto-sync process.