The user receives an ADSTS50107 error when attempting to sign in to Office 365. The full error message reads:

The requested federation realm object 'subdomain.domain.com:exk123456789' does not exist

• Office 365
• Office 365 federation with child domains

The issue occurs for customers with a federation with child domains that was set up before the recent platform update. See Okta Classic Engine release notes (Production) for reference.

The update implemented a fix, but the configuration requires a refresh to apply the changes.

Perform the following steps to apply the fix for the ADSTS50107 error:

1. Go to the Okta Admin Dashboard.
2. Choose Applications > Office 365.
3. Select the Sign On tab.
4. Click Edit.
5. Click Fetch and select.
6. Click Select without modifying any settings.
7. Click Save at the bottom.