Most businesses think Microsoft has them covered

Microsoft 365 is powerful, flexible, and packed with productivity tools. For many companies, it’s the nerve center of communication and collaboration. And because it’s backed by Microsoft, it feels safe.

But that confidence can be misleading. Microsoft 365 offers basic security features — not a full defense strategy. It’s up to your organization to close the gaps.

The default settings aren’t enough

Most organizations assume Microsoft’s default configurations are secure by design. In reality, default tenant settings often leave major exposure points in place. Forwarding rules can be created without notice. Suspicious logins from foreign locations go unflagged. MFA is turned on, but not hardened — leaving it open to fatigue attacks. And mailbox-level visibility? Often nonexistent.

Microsoft provides the tools, but unless they’re configured, tested, and monitored, they don’t protect you.

Microsoft doesn’t monitor your inbox

There’s a common misconception that Microsoft is actively watching for signs of compromise. Unless your organization is paying for — and properly configuring — advanced tools like Defender for Office 365, the platform is passive. Inbound phishing emails that look like they’re from trusted vendors often slip through. Internally compromised accounts may start launching phishing from inside your organization. And login attempts using breached credentials can go undetected for days.

The problem isn’t just that the platform lacks these protections by default — it’s that businesses believe they’re already in place.

You’re still responsible for your data

Even when your infrastructure is hosted by Microsoft, compliance obligations don’t shift. Regulators don’t care where your email is stored — they care how it’s secured.

For regulated industries, that means taking control of:

  • Retention policies and legal hold requirements

  • Encryption of sensitive communications

  • Auditable access controls

  • Threat detection, analysis, and response

The platform gives you the foundation. But the responsibility to secure it — and prove that security — is still yours.

Want help understanding where Microsoft 365 ends and your risk begins? Cloudstar gives you a clear picture and a path forward.