When the Microsoft Office 365 API credentials are authenticated in Okta, the Microsoft login page displays the following error:
 

Sorry, but we're having trouble signing you in.

AADSTS900023: Specified tenant identifier <domainName>.onmicrosoft.com is neither a valid DNS name, nor a valid external domain.
 

• Microsoft Office 365
• API Credentials
• Error

Usually, the Microsoft error results from a misconfiguration of the Office 365 integration added to Okta.

 

Follow the steps or video below.

1. Click on Applications > Applications. 
2. On the Microsoft Office 365 application, click on the General tab.
3. Click on Edit and update the Microsoft tenant to the correct value. 
4. Click Save.

Also, ensure that the Microsoft admin account used to enable provisioning is a non-federated account and that the account is part of the Microsoft tenant specified under the General tab of the Office 365 integration.

Related References

• How to confirm if Okta successfully federated Office 365 with the Okta org
• All Microsoft Office 365 Users that are Part of the Federated Domain Will Be Required to Authenticate with Okta