Microsoft 365 Hardening

Microsoft 365 Security for Small Businesses

Your Microsoft 365 account is the front door to your entire business—email, files, Teams, contacts. Out of the box, it's not locked. Phishing attacks targeting M365 accounts are the most common entry point for business email compromise and data breaches. We harden your setup so those attacks don't get through.

Or email brady@phenicie.com. No phone call required.

Microsoft 365 Security Risks Most Businesses Miss

No multi-factor authentication

MFA is off by default for new accounts. Without it, one stolen password gives an attacker full access to every email, file, and contact.

Legacy authentication enabled

Older protocols like IMAP and POP3 bypass MFA entirely. Attackers specifically target these to get around your authentication requirements.

No email authentication records

Without SPF, DKIM, and DMARC, anyone can send emails that appear to come from your domain. Your clients get fake invoices that look real.

Overly permissive sharing settings

Default OneDrive and SharePoint settings often allow anyone with a link to access shared files—including people outside your organization.

Audit logging off

By default, M365 audit logs may not be configured to retain sign-in and activity data. When something goes wrong, you may not be able to tell what happened.

No phishing simulation training

Employees who've never seen a convincing phishing email are far more likely to click one. Regular simulations train the most important security layer: your team.

What We Configure & Manage

A complete Microsoft 365 security hardening engagement covers every layer of your M365 environment.

Identity & Access

  • Multi-factor authentication (MFA) for all users
  • Conditional Access policies for risky sign-ins
  • Privileged Identity Management for admin accounts
  • Legacy authentication protocol blocking
  • Break-glass emergency access accounts

Email Security

  • Anti-phishing policies with impersonation protection
  • Anti-malware and anti-spam configuration
  • Safe Links and Safe Attachments (Defender for O365)
  • Email authentication: SPF, DKIM, DMARC
  • External email warning banners

Data & File Security

  • SharePoint and OneDrive sharing restrictions
  • Sensitivity labels for confidential files
  • Data Loss Prevention (DLP) policies
  • Guest access controls and review
  • Retention policies for compliance

Monitoring & Response

  • Audit logging enabled and retained
  • Alerts for suspicious sign-in activity
  • Microsoft Secure Score review and improvement
  • Quarterly security configuration reviews
  • Incident response documentation

Microsoft 365 Security FAQ

Is Microsoft 365 secure by default for small businesses?

Not fully. Microsoft 365 has strong controls, but many protections must be configured before they effectively reduce risk.

What is business email compromise (BEC) and how does M365 security reduce it?

Business email compromise happens when attackers gain mailbox access and misuse trusted conversations. MFA, phishing controls, and mailbox monitoring are key defenses.

What Microsoft 365 security settings should every business have?

Core controls include MFA, conditional access, anti-phishing policies, email authentication records (SPF, DKIM, DMARC), and audit logging.

How much does Microsoft 365 security hardening typically cost?

Costs vary by tenant complexity and user count. PBM starts with a targeted review and scopes hardening priorities based on the highest-risk gaps.

Does Microsoft Teams have security risks?

Yes. External access and permissive sharing can introduce risk. Teams security should be configured deliberately with access and meeting controls.

Lock Down Your Microsoft 365 Today

Text SECURE to (406) 957-1576 or email brady@phenicie.com for a free M365 security review. No phone call required.