How to Disable Security Defaults for an O365 Customer (Requires Partner Permissions)
O365 customers created on or after 10/22/2019 have Security Defaults enabled by default. When Security Defaults are enabled all users will be prompted to complete MFA registration upon signing in. Many O365 tenants do not want to have MFA enabled as soon as they start using O365 though so this article will walk you through disabling Security Defaults. To follow the steps in this article you must have Partner access to your O365 customers.
1. Navigate to https://partner.microsoft.com then click Sign In.
2. In the Sign in window enter your O365 partner username then click Next. After this enter your O365 partner password then click Sign in. If you're prompted with MFA, approve the sign in request.
3, Click the Dashboard button to go to the Partner Center.
4. Click CSP then click Customers to load your customer list. In the Customers area enter the company name of the customer in the search bar then press enter. Once the customer appears click the Company Name.
5. In the customer window click Service Management then click Azure Active Directory.
6. In the Azure Active Directory Admin Center click Azure Active Directory then click Properties.
7. In the Properties area click Manage Security Defaults.
8. In the Enable Security Defaults area click No then select the check-box for "My organization is unable to use critical business applications". After this click Save at the bottom of the window.
9. Notify the customer that Security Defaults have been disabled so they should no longer receive an MFA prompt when they sign in. An example notification is listed below.
MFA being enforced automatically is happening because of Microsoft's new Security Defaults. This setting can be found in the Azure Active Directory Admin Center by clicking Azure Active Directory > Properties > Manage Security Defaults > select Yes or No > press Save. We've disabled the Security Defaults for your O365 tenant so you should be able to sign in now without the MFA prompt. Please keep in mind you can re-enable the Security Defaults at any time in the Azure Active Directory Admin Center.