12 Microsoft 365 Security Features and Best Practice Guidance - 3: Defender for Office 365 - Email and Collaboration Protection

What is it?

Microsoft Defender for Office 365 is a cloud based security solution designed to protect your organisation’s Microsoft 365 environment from advanced threats. It focuses heavily on email but also safeguards SharePoint, OneDrive and Microsoft Teams. Features include real time scanning of links and attachments, impersonation detection, phishing protection and post delivery threat investigation.

In short it provides a vital line of defence against common attack methods like phishing, business email compromise and malware laced files.

Why is this important?

Email is still the number one attack vector for cyber criminals. With employees working across multiple platforms and locations the chances of clicking a malicious link or downloading a harmful attachment are higher than ever.

Defender for Office 365 provides proactive tools to stop threats before they reach the inbox. It also supports ongoing investigation and response helping IT teams act quickly when something does get through.

If you’re relying solely on basic Exchange Online Protection you’re leaving the door wide open for targeted attacks. Defender for Office 365 significantly closes that gap.

What plans is it included in?

Defender for Office 365 is available in two tiers:

• Plan 1 – Focuses on prevention tools like Safe Links Safe Attachments and anti phishing policies

• Plan 2 – Includes everything in Plan 1 plus advanced features like automated investigation and response Threat Explorer and Attack Simulation Training

It is also included with:

• Microsoft 365 E5

• Microsoft 365 Business Premium which includes Defender for Office 365 Plan 1.

Licensing can be added on a per user basis so you can protect only the users who need it most if you are not on one of the bundled plans.

Real world scenario

A finance team member receives an email appearing to be from the CFO asking for urgent payment to a supplier. The email looks convincing; correct branding email address is similar and tone of voice matches previous emails.

Without Defender for Office 365 this email might get delivered. But with the anti phishing engine running it detects impersonation patterns and blocks the message.

Even if it were delivered Safe Links would prevent the user from opening any malicious URLs in the email body giving IT extra time to investigate and take action.

How HybrIT can help configure this

At HybrIT we have deployed Defender for Office 365 for clients across both public and private sectors. Our team:

• Reviews your current Microsoft 365 security posture

• Configures baseline policies using Microsoft’s recommended settings

• Customises anti phishing and anti malware policies to suit your organisation

• Sets up automated investigation and response for faster threat remediation

• Runs regular training simulations to boost user awareness

We also work closely with your internal IT or security team to ensure alerts are managed efficiently and nothing slips through the net.

Best practice tips

• Enable Standard or Strict Preset Security Policies for quick deployment of Microsoft recommended settings

• Use Safe Links and Safe Attachments across all supported workloads including Teams and OneDrive

• Run regular phishing simulations to keep users on their toes

• Review Threat Explorer regularly to spot patterns and respond quickly

• Enable user reporting of suspicious emails and integrate it with Microsoft’s automated response tools

📞 Call us on 03330 156 702

📧 Email hello@hybrit.co.uk