Before creating a trust between two Active Directory domains, it is important to consider the following:
- Check that the DNS infrastructure between the two domains is properly set up and that the domains can successfully communicate with each other.
- Check outbound and inbound firewall rules for both the domains.
- Ensure both the domains are using compatible Kerberos versions.
- Check that the version of Windows is the same or higher level in the trusting domain than the trusted domain.
- Ensure that the trust direction fulfils the necessary requirements.
- Verify that computer accounts already exist in the trusted domain.