Applies to: Report Services Suite 2017 (5.4.0) on all supported platforms.

Question:
How to add an account from cross forest one-way selective trust to report services?

Answer:
To enable selective authentication over a forest trust using the Windows interface:

1. Open Active Directory Domains and Trusts.
2. ​In the console tree, right-click the domain node for the forest root domain, and then click Properties.
3. On the Trusts tab, under either Domains trusted by this domain (outgoing trusts) or Domains that trust this domain (incoming trusts), click the forest trust that you want to administer, and then click Properties.
4. ​On the Authentication tab, click Selective authentication, and then click OK.
5. Open Active Directory Users and Computers.
6. Navigate to the Domain Controller the Report Services will use, right-click the computer object, and then click Properties.
7. On the Security tab add the desired user and grant Allow for the Allowed to authenticate permission.

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If the "Allowed to authenticate" is not granted for the specific user the following pop-up will appear:




Please refer to the following Microsoft article with more information on selective authentication:
https://technet.microsoft.com/en-us/library/cc794747(v=ws.10).aspx