Microsoft 365 Security Best Practices for Ohio Credit Unions

I was talking with a credit union leader once when she said something I hear quite a bit.

“Rusty, Microsoft takes care of the security, right?”

My answer was:

“Microsoft takes care of a lot of it. But not all of it.”

And that distinction matters.

Microsoft 365 gives credit unions access to powerful tools like Outlook, Teams, SharePoint, OneDrive, and Microsoft Entra. But moving information into Microsoft 365 doesn’t eliminate your responsibility for protecting it.

Think of it like leasing space in a very secure building.

Microsoft protects the building.

You still have to decide who gets a key, which doors they can open, and what happens when somebody leaves the company.

For credit unions, I recommend focusing on seven areas.

1. Protect Every Account With Strong MFA

If I had to start with one control, it would be identity.

Passwords alone aren’t enough.

Multi-factor authentication adds another layer of verification when someone signs in. And where practical, organizations should move toward phishing-resistant MFA, such as passkeys, FIDO2 security keys, or Windows Hello for Business.

Don’t stop with executives.

Don’t stop with administrators.

Review protection across the entire organization.

And pay particular attention to privileged accounts—the accounts capable of changing security settings or accessing large amounts of information.

2. Use Conditional Access

Not every login attempt should be treated the same.

Someone signing in from their normal work computer is different from somebody attempting access from an unfamiliar device or unexpected location.

Microsoft Entra Conditional Access can help organizations create rules around how users access Microsoft 365.

Depending on your environment, those policies might consider things such as:

• User identity
• Device condition
• Location
• Application being accessed
• Authentication strength
• Sign-in risk

The goal isn’t to make employees jump through hoops.

It’s to make suspicious access harder.

3. Strengthen Email Protection

Email remains one of the easiest ways for attackers to reach employees.

A message that looks like it came from the CEO.

A fake Microsoft login page.

A vendor asking someone to change banking information.

Those attacks don’t need to break through a firewall.

They simply need one person to believe the message.

Microsoft Defender for Office 365 can provide additional protections, including anti-phishing policies, Safe Links, and Safe Attachments.

Safe Links can evaluate suspicious URLs, while Safe Attachments can inspect files for malicious behavior.

But no email filter is perfect.

Technology should be paired with employee education.

4. Review Who Has Access to What

This is where environments quietly become messy.

An employee changes departments but keeps old permissions.

Someone leaves the credit union and a shared account remains active.

An outside vendor receives administrative access for a project and nobody remembers to remove it.

Over time, those small issues create unnecessary risk.

At least periodically, review:

• Administrative accounts
• Former employee access
• Shared mailboxes
• External sharing
• Vendor accounts
• SharePoint permissions
• Teams access

A simple principle helps:

People should have the access they need to do their jobs—and no more.

5. Protect SharePoint, OneDrive, and Teams Too

Sometimes organizations focus so heavily on email that they forget how much sensitive information now lives elsewhere.

Employees share documents through Teams.

Departments store files in SharePoint.

People synchronize information through OneDrive.

Those services deserve the same thoughtful security planning as email.

Microsoft provides protections that can extend into SharePoint, OneDrive, and Teams, but settings still need to be reviewed and managed appropriately.

Remember:

Microsoft 365 isn’t one application.

It’s an ecosystem.

6. Have a Backup and Recovery Conversation

One question I always encourage leadership to ask is:

“If somebody accidentally deleted something important, how would we recover it?”

Then go further.

What if an account were compromised?

What if data were intentionally deleted?

What information does Microsoft retain?

What does your separate backup solution protect?

What are your recovery expectations?

Don’t assume.

Document the answer and test your recovery procedures.

Business continuity doesn’t become less important because your applications moved to the cloud.

7. Monitor, Review, and Improve

Microsoft 365 security isn’t something you configure once and forget.

Employees change.

Threats change.

Microsoft introduces new features.

Your credit union adds vendors and applications.

AI tools such as Copilot may introduce new questions around information access and governance.

That’s why security should be reviewed regularly as part of your broader technology strategy.

Look at:

• Sign-in activity
• Security alerts
• Administrative changes
• Risk findings
• Sharing configurations
• New Microsoft features
• User access
• Incident trends

The goal isn’t to chase every new setting.

It’s to make sure your security posture continues to match your risks.

One Question Every Leadership Team Should Ask

If you’re not sure where your Microsoft 365 environment stands, ask your IT team or technology partner this:

“If someone stole one of our employee’s Microsoft passwords tonight, what would stop them from getting into our information?”

That’s a simple question.

But the answer can reveal a lot.

You may hear about MFA.

Conditional Access.

Device security.

Threat monitoring.

Email protection.

Those are good answers.

If the answer is simply:

“They would need the password.”

Then you have some work to do.

Final Thoughts

Microsoft 365 can be an excellent platform for a credit union.

But security doesn’t happen automatically.

Microsoft provides the tools.

Your organization still needs to configure them thoughtfully, monitor the environment, educate employees, manage access, and plan for recovery.

After more than 26 years working with technology, I’ve learned that good cybersecurity usually isn’t about finding one magical product.

It’s about layers.

Strong identities.

Protected email.

Controlled access.

Educated employees.

Reliable backups.

Ongoing monitoring.

Put those layers together, and Microsoft 365 becomes more than a productivity platform.

It becomes part of a thoughtful strategy for protecting your employees, your operations, and most importantly, your members.

Is Your Credit Union Getting the Most Security From Microsoft 365?

At CTG, we help credit unions review Microsoft 365 from the perspective that matters most: Is it configured to support your people while protecting your organization?

We can help evaluate identity security, MFA, Conditional Access, email protection, Microsoft 365 permissions, backup strategy, cybersecurity monitoring, and how Microsoft 365 fits into your broader technology roadmap.

For more than 26 years, CTG has helped organizations make practical technology decisions, backed by a team with more than 200 years of combined experience.

Talk with CTG

Phone: 330-655-8144
Email: brett.harney@ctgusa.net
Website: ctgusa.net

Let’s make sure Microsoft 365 isn’t simply working for your credit union.

Let’s make sure it’s working securely.