Information
This policy setting activates Office on users computers without prompting them to sign in to their Office 365 accounts.
If you enable or do not configure this policy setting, and a user is already signed in with federated organization credentials, Office automatically activates when the user first starts an Office application. If either multiple or no organization credentials are found, the user is prompted to sign in.
If you disable this policy setting, Office might prompt the user to sign in with their organization's credentials if Office is not installed directly by the user from his or her Office 365 account homepage.
Solution
Policy Path: Microsoft Office 2016\Subscription Activation
Policy Setting Name: Automatically activate Office with federated organization credentials