My company is still using Windows Server 2003 for the Domain Controllers, with DFL (and FFL) already raised to 2003 DFL/FFL.
Now, we need to trust the domain of our new subsidiary. Their domain is using Windows Server 2012 (not R2) for their DCs, with 2012 DFL/FFL.
Do we need to run adprep.exe from 2012 on our 2003 DCs to establish the trust relationship?