Please verify all steps first, as most Active Directory problems come from an issue during replication. Please do the following steps:

1) Please download the latest firmware from the Support Website ( http://support.acer-euro.com/drivers/server/altos_easystore.html )
2) Get back to local authentication mode if AD Mode was already setup
3) Upgrade the firmware with the new downloaded version
4) In local authentication mode, please change the netbios name of the easystore into a new one like MAIN-EASYSTORE. To do this log into the WEB Gui and go into Advance, System section and change it.
5) Please set the NTP server in Advanced,System section. The IP Address is the IP of the Domain Controller. Please set manually the TimZone instead.
6) Check the TimeZone on the Domain Controller, to be sure is set correctly.
7) Start the synchronization with the Active Directory. Please always use the IP Address of the DC and not the name.
8) Create a folder and apply user access