Hi Gian,
Firstly, please change objectCategory from “user” to “Person”, since with an object filter of objectClass=user, ADAMSync will synchronize users and computers (and contact objects and anything else that inherits from the User class).
If the issue persists, please perform a full schema import using ADSchemaAnalyzer; if the process fails, please post out related error messages for further troubleshooting.
Detailed steps can be found in these articles below:
Synchronize Active Directory to ADAM with ADAMSync (step-by-step)
Create Custom Directories with ADAM
https://technet.microsoft.com/en-us/magazine/2006.07.customdir.aspx
ADAMSync 101
http://blogs.technet.com/b/askds/archive/2012/11/12/adamsync-101.aspx
Best Regards,
Amy
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