What are some easy ways to enhance email security in Office 365 E3?

Just a heads-up, E3 licenses have some limitations. For example, you might not have access to Defender for Office 365 or Intune features. It could be worth looking into Microsoft 365 licenses for more comprehensive security options. The E3 plan is pretty basic in terms of security capabilities.

One of the key steps is to promote security awareness among users. It's essential to educate everyone about phishing and other threats. You could even simulate phishing attacks to gauge employees' responsiveness. Awareness is the first line of defense!

Consider implementing Multi-Factor Authentication (MFA) and setting up conditional access policies. You should also explore options like mail flow rules and enable auditing for better insights on activities within your email environment. These measures can help bolster your security significantly.