The client

A leading independent school in Hertfordshire required stronger protection across its Microsoft 365 email environment as phishing attacks, impersonation attempts and malicious email activity continued to increase.

Like many educational organisations, the school stored significant volumes of sensitive information relating to staff, parents and students; making email security a critical operational and safeguarding concern.

Peritus Cloud Security partnered with the school to modernise its email security posture through Mimecast, delivering enhanced threat protection, reduced spam exposure and improved operational resilience.

The challenge

The school experienced a growing volume of:

• phishing attempts
• impersonation attacks
• malicious attachments
• harmful URLs
• spam and unwanted email activity

As cyber attacks targeting the education sector became more sophisticated, protecting staff and students from email-based threats became increasingly important.

The organisation needed a solution that could:

• reduce malicious email exposure
• improve phishing protection
• strengthen safeguarding controls
• reduce operational overhead
• remain easy for staff to use within a busy school environment

Email remained one of the organisation’s highest-risk attack vectors, particularly as users became increasingly desensitised to spam and suspicious messages.

The Peritus approach

Peritus Cloud Security deployed Mimecast as part of a managed email security and threat protection programme designed specifically for the organisation’s Microsoft 365 environment.

The engagement focused on improving visibility, reducing user exposure to malicious content and simplifying operational management for internal IT teams.

Advanced email threat protection

Peritus implemented Mimecast Email Security to strengthen protection against:

• phishing attacks
• spoofing attempts
• malicious attachments
• harmful URLs
• spam campaigns

Reduced spam and impersonation risk

Following deployment, the school experienced a substantial reduction in spam emails reaching end users alongside improved prevention of impersonation and spoofing attacks.

Improved user experience

The platform’s simplified user experience reduced the need for extensive staff training and improved adoption across teaching and administrative teams.

Safeguarding and operational resilience

By reducing exposure to malicious email activity, the organisation strengthened protection for students, staff and sensitive organisational data.

The outcome

Following deployment, the school achieved measurable improvements across email security visibility, threat prevention and operational efficiency.

Key outcomes included:

• Significant reduction in phishing attempts reaching inboxes
• Improved prevention of spoofing and impersonation attacks
• Reduced malicious attachment and harmful URL exposure
• Major decrease in spam email volume
• Simplified operational management for internal IT teams
• Reduced reliance on manual user awareness intervention
• Improved safeguarding posture for students and staff

Security metrics observed

• 59,267 spam emails blocked
• 18,355 impersonation attacks stopped
• 531 malware attacks detected and rejected
• 118 malicious attachments blocked
• 3,994 harmful URLs blocked

Client feedback

“Mimecast is by far one of the best email protection platforms available. The reduction in phishing and spam has been significant, and the platform has been extremely effective for our school environment.”

- Director of ICT, Hertfordshire Independent School

Why Peritus

Peritus Cloud Security combines enterprise-grade security technologies with operational consultancy and managed cybersecurity expertise.

By combining Mimecast’s advanced email security capabilities with Peritus-led deployment and operational support, the organisation gained a scalable and effective email protection capability aligned to the safeguarding and operational requirements of the education sector.

The tone, layout direction and presentation style align with the Peritus brand system: enterprise-focused, restrained, technically credible and visually controlled.

‍