Dynamics 2012 user import from active directory issue

Im newbie on this. I have the installation done until now, but when trying to import users im getting this error message:

The Active Directory domain controller name ecommgrp.local cannot be reached. Verify your permissions and network connectivity.

I had my AOS service running under NETWORK SERVICE  account and i changed to LOCAL SERVICE account, but still the same.

Any ideas?

Thanks in advance.