Microsoft 365 Security Defaults are a range of settings and controls that helps to protect an organisation from user account attacks. The main benefit of Security Defaults is that it requires all users to enable Multi-Factor Authentication.


As well as enabling MFA, Security Defaults disables legacy applications including IMAP, SMTP and POP email protocols. This means services such as scan to email or sending email from websites may be affected. It is important to discuss this with the Lineal team before enabling the setting.


Security Defaults is included as part of all Microsoft 365 plans and enabling the setting incurs no extra cost.