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Open Active Directory Domains and Trusts.
In the console tree, right-click the domain node for the forest root domain of the forest for which you want to establish an incoming forest trust, and then click Properties.
On the Trusts tab, click New Trust, and then click Next.
On the Trust Name page, type the Domain Name System (DNS) name of the forest root domain of the other forest, and then click Next.
On the Trust Type page, click Forest trust, and then click Next.
On the Direction of Trust page, click One-way: incoming, and then click Next.
For more information about the selections that are available on the Direction of Trust page, see "Direction of Trust" in Appendix: New Trust Wizard Pages.
On the Sides of Trust page, click This domain only, and then click Next.
For more information about the selections that are available on the Sides of Trust page, see "Sides of Trust" in Appendix: New Trust Wizard Pages.
On the Trust Password page, type the trust password twice, and then click Next.
On the Trust Selections Complete page, review the results, and then click Next.
On the Trust Creation Complete page, review the results, and then click Next.
On the Confirm Incoming Trust page, do one of the following:
- If you do not want to confirm this trust, click No, do not confirm the incoming trust.
- If you want to confirm this trust, click Yes, confirm the incoming trust, and then supply the appropriate administrative credentials from the specified domain.
On the Completing the New Trust Wizard page, click Finish.
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