How to disable security defaults in Office 365?

Enabling the Security defaults will also change how you (admin) or your users will login to Office 365 and its services as outlined below.

1. Prevents less secure apps from logging into your account and also prevents legacy authentication from outdated email clients. It also restricts access if you want to login via IMAP, POP3, SMTP, or Remote PowerShell.
2. Enables Multi Factor Authentication for all users, prompting them to configure MFA during sign-in.
3. Enforces MFA for privileged accounts in the Azure Active Directory to access Azure CLI, Azure Portal and so on.

Furthermore, if you intend to use Conditional Access policies (where you can customize the security settings), you must first disable the security defaults before configuring the Conditional Access policies.

Enable or disable Security defaults step-by-step

You can enable or disable the security settings at any time through Microsoft's Azure portal. Authentication to your Office 365 account may fail even if you have enabled MFA and App Password.

Users also get the following prompt on their Office 365 login page “Microsoft has enabled security defaults to keep your account secure”

In all the aforementioned cases, it is necessary to disable security defaults. Keep in mind that changing these settings requires you to login to your tenant as a global administrator.

• Step 1: Login to Office 365 using global administrator credentials.
• Step 2: Click on 'Admin' (gear icon) from the left panel

  

• Step 3: Click on 'Azure Active Directory' under Admin centers

  

• Step 4: Click on 'Properties' from the left panel
• Step 5: Click on the 'Manage Security defaults' link
• Step 6: Toggle the 'Enable security defaults' to 'No' and click 'Save'. (If you want to enable the settings, toggle it to 'Yes')

  

After disabling the security settings, you will no longer be prompted with the MFA configuration during sign-in.

Enable access to basic authentication protocols

If you're having trouble connecting to your IMAP / POP accounts (Gmail, Hotmail, Outlook) from your email clients, make sure you've enabled access to legacy authentication protocols. Here's how to do it step by step.

• Step 1: Login to Office 365 using global administrator credentials.
• Step 2: Click on 'Admin' (gear icon) from the left panel
• Step 3: Click on the Navigation menu on the top left, click 'Show All', expand 'Settings' and click on 'Org Settings'.

  

  

• Step 4: Under Modern authentication, select all the protocols you would like to enable and click 'Save'.

  

Now, you will be able to allow your email clients to access your account or connect using IMAP.