Modernizing the message: What the future of email means for your IT strategy
4 June 2025
0 min read
Email runs everything. It’s central to operations but often built on infrastructure that hasn’t kept up.
Legacy email systems are becoming weak points in today’s IT stack, introducing risks and inefficiencies that hinder progress. To keep pace with modern demands, IT leaders need to ensure email is secure, well-integrated, and actively managed as a core part of their infrastructure.
As Microsoft shifts to Exchange Server Subscription Edition (SE), IT leaders are being pushed to treat email infrastructure like any other modern system. That means reducing technical debt, removing manual processes, and managing every layer from security to signatures with control and precision.
Email plays a foundational role in how businesses operate. It should be secure, connected, and operationally efficient. Register now to get ahead of Microsoft’s changes and stay in control before the deadline.Join our webinar
The real risk of outdated email infrastructure
Legacy systems don’t operate on their own. They connect to clients, security tools, archiving platforms, and routing policies. When the core is out of date, the rest inherits the same limitations.
In fact, according to a recent report conducted by Exclaimer, 83% of organizations experienced an email-related security incident, and nearly half occurred in just the past year. Despite the known risks, fewer than one-third have implemented protections like DMARC, DKIM, or SPF, leaving core email systems exposed to spoofing, phishing, and impersonation attacks.
And as the rest of your environment moves forward, these systems fall further behind.
Common issues include:
Patch lag and security gaps: Older platforms often fall behind on critical updates. This creates known vulnerabilities that can’t be fixed without full version upgrades. Encryption standards, authentication protocols, and TLS support also age out quickly.
Limited threat protection: Manual rules and bolt-on filters aren’t designed to stop modern phishing, spoofing, or zero-day threats. Without integration into real time threat intelligence, detection lags behind attack tactics. In fact, 44% of IT leaders cite external threats like phishing and spoofing as top challenges, yet many lack automated, policy-driven defense systems.
Compliance and audit risks: Without visibility and control, email disclaimers go missing, routing becomes opaque, and retention fails under pressure. Audits are harder. Fines are likelier. Only 47% of IT leaders say they’re very confident in their compliance posture, and enforcement is still largely manual—46% struggle with data retention and 44% with user behavior management.
Disconnected systems: Many legacy stacks are a patchwork of mail servers, SMTP relay nodes, signature tools, and archiving systems that don’t integrate well with each other or with modern platforms like Microsoft 365. Each disconnected tool creates its own failure point and increases the support burden on IT. Only 41% of IT leaders report integrating email with their security and compliance stack, and just 29% have automated workflows.
Operational inefficiencies: IT teams spend time carrying out manual tasks with scripts, applying ad hoc rules, or troubleshooting breakage caused by version mismatches. Managing email signatures alone is one of the top two most time-consuming tasks for 35% of IT leaders, reflecting just how deeply inefficiencies are embedded in outdated infrastructure.
“When the core is out of date, the rest of the stack inherits the same limitations. One legacy service affects everything it touches.”
The legacy layer beneath business email
Even when the core server is patched, the layers around it often tell a different story. Many still run software that made sense ten years ago but doesn’t today.
These systems stick around because they work. But they also slow teams down, make fixes harder, and introduce hidden dependencies that are easy to miss until something breaks.
Common components include:
Exchange Server 2016 or 2019: These versions of Exchange continue to run in many environments but will lose support from Microsoft in October 2025. This will create security gaps and dependency issues. Many customers also delay cumulative updates, which increases the chance of known exploits being used against them.
Legacy archiving tools: Older archiving systems were built for compliance rules that have since changed. They often lack modern encryption, retention automation, or the ability to index newer file formats and communication data types. Search performance is slow, and exports are limited in scope and formatting. This makes audit response and eDiscovery more difficult.
Manual email signature management: Signatures managed through scripts or group policy are labor intensive. They break easily, rely on IT involvement for every change, and often lack support for modern devices and mobile clients. There’s no central visibility into what email signatures are in place or whether they meet brand or compliance guidelines.
On premises SMTP servers: Many organizations still use dedicated SMTP servers for mail relay. These often serve legacy applications or workflows that haven’t been modernized. But without full monitoring or patching, they’re easy to overlook and easy to exploit.
Standalone antispam tools: Some teams use third-party filtering products with limited integration into broader email security systems. These tools don’t use shared signals or threat intelligence from Microsoft or Google. Instead, they create blind spots and can’t adapt to advanced phishing or zero-day campaigns.
“Legacy email failures are visible. They create disruption users notice and raise questions IT doesn’t want to answer.”
What a modern email stack looks like
Modern email infrastructure is built to reduce risk, simplify operations, and support a cloud-based architecture. It replaces patchwork systems with integrated services that are easier to manage, more adaptable over time, and aligned with compliance needs. This approach gives IT full visibility and control while reducing reliance on unsupported or custom solutions.
Platforms like Exclaimer already help IT teams modernize email signature management within this stack:
Microsoft 365 and Google Workspace: These platforms offer native cloud delivery, built-in redundancy, and continuous feature updates. They reduce maintenance overhead and improve reliability. Identity, device management, and threat protection are fully integrated.
Centralized email signature management: Signatures are managed centrally across all users and devices. IT teams control formatting, disclaimers, and legal footers while giving marketing teams the ability to update campaigns and branding without requiring manual updates or desktop installs.
Integrated security tools: Security features like multifactor authentication, phishing detection, and data loss prevention are built into the platform and updated continuously. They use real-time signals from millions of endpoints, not static rules.
AI for triage and threat response: Cloud-based platforms can apply machine learning to detect abnormal behavior, route emails intelligently, and isolate potential threats before they spread. This adds a layer of protection beyond keyword filters or IP blocklists.
Built in archiving and compliance: Modern platforms include searchable, immutable archives with role-based access, audit logs, and automated retention policies. Legal holds and eDiscovery are available without requiring third party systems.
Risks: Missing patches, inconsistent signatures, lack of support. Benefits: Lower risk, improved consistency, fully supported.Email infrastructure: Then vs. now
Legacy email stack
Modern email stack
Why this matters now
If your email systems fall behind, everything connected to them starts to break. Legacy systems don’t meet the expectations placed on IT today. Security teams need tools that adapt. Compliance teams need consistent data. Executives want systems that work across every device and location. Older infrastructure wasn’t built for any of this.
Threats are more sophisticated: Attacks now target common gaps across legacy mail servers and manual configurations. Static filters and disconnected tools can’t respond fast enough. Threat actors exploit unpatched vulnerabilities, weak authentication, and blind spots in hybrid environments.
Compliance requirements are stricter: Audits demand full traceability, reliable records, and consistent enforcement of policies. Unsupported systems make that difficult. Retention rules, access controls, and email signature consistency all matter. And they all break down faster without centralized management.
Executives and end users expect better: Broken signatures, blocked mobile access, or inconsistent delivery create visible friction. IT teams are expected to deliver systems that are resilient, accurate, and easy to use—without extra support requests or downstream fixes.
“Waiting narrows your options. Acting now gives you control.”
Email infrastructure doesn’t fix itself
Legacy email tools often stay in place because they still work. But they slow teams down, create risk, and take up time IT could use elsewhere.
In otherwise modern environments, they stand out. They introduce inconsistencies. They rely on manual effort. And they’re easy to forget until they fail.
Auditing your email stack is a practical first step. Identify what’s still running, what’s out of support, and what’s getting harder to maintain. Then decide what you need to move, retire, or replace.
Register now to get ahead of Microsoft’s changes and stay in control before the deadline.Plan your next move—join our webinar for clarity on Exchange SE
