Why the SEG Stopped Working for MSPs

Albert Einstein is notoriously cited for stating, “Insanity is doing the same thing over and over again and expecting different results.” Why would email security be any different?

It’s 2025 and the Managed Service Provider (MSP) market continues to utilize a Secure Email Gateway (SEG) to tackle the growing phishing problem. One might chalk it up to convenience, a false sense of comfort, or simply maintaining the status quo, but the phishing threat is only getting worse.

MSPs are under more pressure than ever to safeguard their clients from today’s email-based attacks. However, legacy tools like SEGs are falling short in the fight against modern phishing attacks. This issue isn’t one-sided, as threat actors continuously refine phishing strategies to exploit new enterprise vulnerabilities. SEGs continue to improve upon their advanced phishing detection, pre-delivery approach, and rule-based methodology, but what if the SEG's core model isn’t enough for today’s attacks?

While SEGs have limitations, they still offer value in specific areas. Pre-delivery management, email encryption, and archiving are still features needed by MSPs and generally offered by the market-leading SEGs. MSPs can find the latter two features in workspace solutions like Google Workspace (GWS) and Microsoft 365 (M365). But pre-delivery detection and data security are just two of the litany of tools available to today’s MSP to help tackle the email security problem.

MSPs need to consider an Integrated Cloud Email Security (ICES) platform to effectively tackle today’s email security problems. I’m going to walk you through the key differences between a SEG and ICES platform as well as highlight the key value drivers you can expect from leading ICES vendors like IRONSCALES.

Let’s start with the basics…

What is a SEG?

A Secure Email Gateway (SEG) is a perimeter-based solution designed to monitor and filter inbound and outbound email traffic. Typically, it functions as a checkpoint, analyzing emails for spam, viruses, and other malicious content before delivering them to recipients (pre-delivery management). While SEGs were effective in simpler threat environments, they struggle to keep up with today’s increasingly sophisticated attacks, such as business email compromise (BEC), account takeovers (ATOs), and spear phishing.

Top 10 Reasons Why SEGs Are No Longer a Good Fit for MSPs

1. Static, Rule-Based Detection
   SEGs rely heavily on predefined rules and signatures. While effective for less advanced email threats, this approach has been largely ineffective against dynamic phishing techniques like zero-day and social engineering attacks.
2. Limited Visibility into Cloud Email Platforms
   As businesses migrate to platforms like M365 and GWS, SEGs can't natively integrate, leading to blind spots in detecting internal threats.
3. Lack of User-Context Awareness
   SEGs lack the ability to analyze user behavior or email context, leaving them vulnerable to sophisticated social engineering attacks. Ongoing cyber education is a key aspect of maintaining a resilient organization.
4. Latency Issues
   By routing emails through an external gateway, SEGs introduce delivery delays that frustrate users and disrupt business workflows.
5. High Management Overhead
   MSPs often need to spend excessive time configuring and maintaining SEGs to keep them operational, which eats into the MSPs overall profitability.
6. False Positives and Negatives
   Over-reliance on static filtering leads to false positives (blocking legitimate emails) and false negatives (missing phishing threats), both of which erode client trust and create greater operational interruption for the MSP's end users.
7. Weak Post-Delivery Remediation
   If a malicious email bypasses the SEG, there is generally little to no functionality for detecting and removing it post-delivery.
8. Inefficiency Against Emerging Threats
   SEGs can’t adequately address multi-vector attacks or those targeting multiple stakeholders within an organization.
9. Complex Integration with Other Tools
   SEGs struggle to seamlessly integrate with modern security ecosystems, limiting an MSP’s ability to provide cohesive client solutions.
10. Expensive and Outdated Deployment Models
    SEGs often require hardware or appliance-based installations, increasing costs and reducing scalability for the MSP.

SEGs fall short in addressing the challenges of modern email security, leaving MSPs ill-equipped to combat increasingly sophisticated phishing tactics and cloud-based threats. Their limitations create blind spots, operational inefficiencies, and missed opportunities for proactive threat detection, ultimately creating higher risk. MSPs need solutions that prioritize adaptability, seamless integration, and AI-driven capabilities to protect against advanced email-based attacks. 

MSPs need an ICES solution…

What is an ICES?

Integrated Cloud Email Security (ICES) is a modern approach to email protection designed to seamlessly integrate with cloud-native platforms like M365 and GWS. Instead of relying on static rules, ICES solutions use advanced machine learning, AI, and contextual analysis to detect and mitigate email-based threats. They operate within the email platform itself, offering real-time threat detection, user training, and post-delivery remediation.

Why MSPs Should Prioritize ICES Over SEGs?

• Cloud-Native Integration
  Unlike SEGs, ICES platforms work directly within cloud email environments, eliminating blind spots and ensuring end-to-end visibility.
• AI-Powered Threat Detection
  ICES leverages AI and machine learning to detect sophisticated attacks in real time, adapting to evolving threats without manual rule setting.
• Post-Delivery Protection
  Even if a threat bypasses initial defenses, ICES can identify and remediate it post-delivery, minimizing the risk of a breach.
• User-First Design
  ICES emphasizes user training and phishing simulations to reduce human error – often the weakest link in email security. The human element can never be eliminated, but it can be reduced by improved cyber education programs.
• Lower Management Overhead
  ICES platforms automate threat analysis and remediation, allowing MSPs to focus on delivering value rather than micromanaging tools for their clients.

IRONSCALES: The ICES Solution Built for MSPs

We offer an AI-driven, integrated platform that is recognized as a visionary ICES platform for a reason. We designed our Adaptive AI email security to defend against modern threats and address the gaps left by traditional SEGs. Here’s why MSPs managing email security for their clients should consider the IRONSCALES email platform:

• AI-Driven Detection and Response
  We use advanced AI to detect and respond to phishing attacks, including those that exploit human psychology, in real-time.
• Integrated Post-Delivery Remediation
  MSPs can quickly remove malicious emails even after they’ve landed in inboxes, reducing the risk of a successful attack. These malicious emails are then subsequently removed from other impacted inboxes to further reduce risk.
• Seamless Cloud Integration
  Designed to work natively with M365 and GWS, our platform provides unmatched visibility and control.
• Integrated Platform Approach
  In-platform security training and industry-leading phishing simulation tools to empower end users to identify and report phishing attempts.
• Multi-Tenant Management
  Purpose-built for MSPs, our platform offers centralized management, reporting, and analytics for multiple client environments making it easy to manage clients environments at scale.

Conclusion

In today's unpredictable phishing environment, SEGs are no longer the right solution to provide the level of protection MSPs and their clients require. ICES platforms like IRONSCALES offer a proactive, AI-driven approach that is perfectly suited to the needs of MSPs. By adopting the IRONSCALES platform, MSPs can grow their business efficiently, increase end-user cyber education, improve operational efficiency, and deliver an outstanding email security experience for their clients.

Discover how IRONSCALES can help your business move beyond SEGs. Learn more about the IRONSCALES MSP/MSSP Partner Program today.