@Jeremiah Johnson Thank you for reaching out to us, As I understand you want to disable microsoft authenticator app requirement for Office 365 users.
Though it is not a recommended option from security standpoint, you can achieve this ask via below steps
To disable Microsoft Authenticator for your users, you can manage the Authentication methods policy. This policy is the recommended way to manage Microsoft Authenticator. Authentication Policy Administrators/Global Administrators can edit this policy to enable or disable Microsoft Authenticator. Admins can include or exclude specific users and groups from using authenticator app.
After you disable Microsoft Authenticator from Authentication methods policy, your users will no longer be prompted to use it for authentication. However, they will still be able to use other authentication methods that are enabled in the policy.
Also make sure you have registration campaign option disabled as well - https://learn.microsoft.com/en-us/entra/identity/authentication/how-to-mfa-registration-campaign
Reference: https://learn.microsoft.com/en-us/entra/identity/authentication/concept-authentication-methods
Let me know if you have any further questions, feel free to post back.
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