Microsoft 365 is much more than Outlook, Word, Excel, and Teams. It also includes security capabilities designed to help businesses protect user identities, company data, devices, email, and cloud applications.
But simply having Microsoft 365 does not mean every important security control is configured correctly.
Microsoft itself recommends that businesses review security settings, protect identities with multifactor authentication, secure devices, and assess their overall security posture. Microsoft 365 Business Premium Security Guide highlights tools including Microsoft Defender, Microsoft Entra ID, Microsoft Intune, Defender for Office 365, and Microsoft Purview.
For a small business, the following eight areas are worth reviewing regularly.
1. Multifactor Authentication (MFA)
A username and password alone should not be the only protection around your Microsoft 365 accounts.
Multifactor authentication adds another verification step when a user signs in. Microsoft specifically recommends setting up MFA as part of protecting identities in Microsoft 365 Business Premium.
This is particularly important for accounts with administrative access.
What to review
- Which employees are protected by MFA?
- Are administrator accounts protected?
- What authentication methods are users registering?
- Are there old or unnecessary accounts that can still sign in?
Dadala Group recommendation: Treat MFA as a basic requirement for Microsoft 365 access rather than an optional extra.
2. Microsoft Entra ID Security Settings
Microsoft Entra ID manages identities and access to Microsoft 365 services.
For smaller organisations without more advanced identity policies, reviewing Microsoft’s security defaults can provide an important baseline. Microsoft’s small-business security guidance specifically recommends reviewing Microsoft Entra default security settings or configuring appropriate alternatives.
Businesses using more advanced configurations can also use Conditional Access to apply more granular rules. Microsoft’s practical Microsoft 365 security guidance includes Conditional Access as part of its identity protection checklist. Practical Guide to Securing Work From Anywhere Using Microsoft 365 Business
What to review
Check how your organisation handles:
- User authentication
- Privileged administrator access
- Legacy or outdated access methods
- Authentication registration
- Access policies
Identity security should be one of the first areas reviewed after setting up a Microsoft 365 tenant.
3. Administrator Accounts and Permissions
Not everyone who occasionally performs an administrative task needs unrestricted administrative access.
A compromised administrator account can potentially expose far more of the environment than an ordinary user account.
Microsoft’s Microsoft 365 security guidance recommends applying the principle of least privilege and planning specifically for administrative accounts.
Small businesses should therefore periodically review who has administrative permissions.
Ask yourself:
Who currently has administrator access, and do they still need it?
Permissions that were granted temporarily for a project, supplier, consultant, or former employee should not remain indefinitely without a business reason.
4. Email Protection and Anti-Phishing Settings
Email remains one of the most important security areas to protect because employees regularly receive messages containing links, attachments, invoices, password-reset requests, and other business communications.
Microsoft Defender for Office 365 provides security capabilities designed to protect email and collaboration environments. Microsoft provides recommended security settings and preset security policies as part of its Defender for Office 365 guidance. Microsoft Defender for Office 365 documentation
Depending on your Microsoft 365 licensing and configuration, review your protection against:
- Phishing
- Malicious attachments
- Suspicious links
- Spoofing
- Unwanted email
Security controls should also be reviewed periodically rather than assuming the original configuration remains appropriate forever.
5. SPF, DKIM and DMARC
Your company’s domain is part of your business identity.
If another party attempts to send an email pretending to originate from your organisation, properly configured email authentication can help receiving systems determine whether the message is legitimate.
Three important technologies to review are:
SPF (Sender Policy Framework)
Helps specify which systems are authorised to send email for your domain.
DKIM (DomainKeys Identified Mail)
Provides a way for receiving systems to validate outbound email associated with your domain.
DMARC (Domain-based Message Authentication, Reporting and Conformance)
Builds on SPF and DKIM and provides policies for handling authentication failures.
Microsoft’s Defender for Office 365 documentation specifically provides guidance for configuring SPF, DKIM, and DMARC.
If your business uses services other than Microsoft 365 to send email, such as marketing, CRM, invoicing or support platforms, these should also be taken into account when the domain’s email authentication is configured.
6. Device Security and Microsoft Intune
Your Microsoft 365 security strategy should not stop at email.
Think about the devices employees use to access:
- Outlook
- OneDrive
- SharePoint
- Teams
- Company documents
- Other cloud applications
Microsoft Intune can help organisations manage devices and apply rules governing access to company resources across supported device platforms. Cybersecurity for small and medium business
Microsoft’s security guidance also highlights device enrollment, compliance policies, application protection and device-based Conditional Access as areas businesses should consider.
For small businesses, this means asking an important question:
Do we know which devices are accessing our business information, and are those devices appropriately protected?
7. External Sharing and Guest Access
Microsoft 365 makes collaboration easy, but convenience should be balanced with control.
Documents can be shared through services such as OneDrive and SharePoint, while external users can potentially collaborate through Teams depending on your organisation’s configuration.
Over time, businesses can accumulate external users, sharing links and permissions that are no longer required.
Microsoft’s security guidance specifically includes areas such as Teams guest access, external chat and related collaboration controls in its recommended security review items.
Businesses should periodically review:
- External and guest users
- Shared documents
- External sharing policies
- Old sharing links and permissions
- Teams guest-access requirements
The objective isn’t to prevent collaboration. It is to make sure access exists because someone still needs it.
8. Microsoft Secure Score
If you are wondering“Where should we start?”, Microsoft Secure Score is a useful place to look.
Microsoft describes Secure Score as a measurement of an organisation’s security posture. It provides recommended actions and helps organisations monitor security across Microsoft 365 identities, applications and devices. Microsoft Secure Score
However, a higher score should not become the only goal.
Microsoft notes that security needs to be balanced with usability and that not every recommendation will be appropriate for every environment.
Use Secure Score as a security improvement roadmap, not simply as a number to maximise.
Microsoft 365 Security Is Not “Set and Forget”
One of the biggest mistakes a small business can make is assuming that because Microsoft 365 is a cloud service, Microsoft automatically manages every aspect of the organisation’s security configuration.
The platform provides powerful security capabilities, but businesses still need to review how identities, devices, email, data and external access are configured.
Microsoft’s own Microsoft 365 Business Premium guidance brings together protections covering identities, devices, email, collaboration and data.
A sensible Microsoft 365 security review should therefore include:
- Multifactor authentication
- Microsoft Entra ID security settings
- Administrator permissions
- Email and phishing protection
- SPF, DKIM and DMARC
- Device security and Microsoft Intune
- External sharing and guest access
- Microsoft Secure Score
Even small improvements across these areas can create a more controlled and manageable Microsoft 365 environment.
Not Sure Whether Your Microsoft 365 Environment Is Properly Secured?
Many businesses use Microsoft 365 every day without knowing whether important security features have been reviewed or configured appropriately.
Dadala Group can help your business review its Microsoft 365 security configuration and identify practical areas for improvement.
Our Microsoft 365 and cybersecurity services can assist with areas such as:
- Microsoft 365 security reviews
- Microsoft Entra ID and identity security
- Multifactor authentication
- Microsoft Intune and device management
- Microsoft Defender security
- Email security
- Microsoft 365 administration
- Security configuration and ongoing IT support
Protect your Microsoft 365 environment before a problem becomes an incident.
Contact Dadala Group to discuss a Microsoft 365 Security Review.
