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Microsoft 365 Tenant Security

Your M365 tenant is your business. Harden it like it.

The problem

The M365 tenant holds identity, email, files, and collaboration — the crown jewels — yet most tenants run on defaults set at creation and never revisited. Legacy authentication lingers, external sharing is unbounded, admin roles accumulate, and mail security relies on out-of-box policies. Attackers know all of this; tenant compromise is now a commodity attack.

Our approach

A structured hardening program across the tenant's control planes: identity (Entra ID, Conditional Access, PIM, MFA), collaboration (Exchange, Teams, SharePoint and OneDrive sharing architecture), endpoints (Intune baselines and compliance), and monitoring (audit, alerting, Secure Score tracking). Assessed first, prioritized by exploitability, rolled out in staged waves with user impact managed deliberately.

What we do

  • M365 tenant security assessment
  • Entra ID hardening & Conditional Access design
  • MFA / phishing-resistant auth rollout
  • Legacy authentication elimination
  • Admin role rationalization & PIM
  • Exchange Online protection & email authentication (SPF/DKIM/DMARC)
  • Defender for Office 365 configuration
  • Teams & SharePoint sharing governance
  • OneDrive & external collaboration controls
  • Intune security baselines & device compliance
  • Tenant audit & alerting configuration
  • Secure Score improvement program

What you receive

  • Tenant assessment report with prioritized findings
  • Conditional Access architecture & rollout plan
  • Admin role model with PIM configuration
  • Email security configuration with DMARC roadmap
  • Collaboration sharing governance design
  • Intune baseline set
  • Before/after Secure Score evidence
  • Operations handbook for ongoing tenant security

What changes for the business

  • Dramatically reduced account compromise risk
  • Email domain protected against spoofing
  • Controlled external sharing without killing collaboration
  • Managed, compliant devices as an access condition
  • A tenant configuration you can show auditors and insurers

Who this is for

Any organization on M365 that has never had an independent tenant review; companies post-incident or post-phishing-scare; firms facing cyber-insurance security questionnaires; IT teams inheriting tenants from previous management or MSPs.

Common questions

How is this different from your broader Microsoft Security services?

This is the focused, fixed-scope M365 tenant program — the most common starting engagement. The broader security practice covers Azure workloads, XDR, and Zero Trust programs.

We use an MSP — do we still need this?

Often yes. MSPs administer; independent security review validates. We frequently work alongside incumbent MSPs.

How fast do quick wins land?

High-impact items — legacy auth, admin MFA, mail authentication records — typically land within the first weeks of remediation.

What size tenant do you work with?

Typically 250+ seats; the methodology scales to very large multi-geo tenants.

Will you lock us out?

Break-glass accounts, staged policy rollout, and report-only validation are standard in every engagement. Availability is a design requirement, not an afterthought.