Email security shouldn't break your mail flow (or your brain)

Let's be honest - nobody wants to mess with MX records.

They're fiddly. Risky. And just one typo away from bouncing your entire company's email into the void. But most email security providers still rely on them to get protection in place. It's been that way for years. And IT teams have just... dealt with it.

But now that most organisations are deep in Microsoft 365, does that setup still make sense? Or are we all just holding onto a process that causes more stress than security?

Here's a look at why MX-based email security is long overdue for retirement - and what a modern alternative actually looks like.

A brief history of email security pain

MX records direct where email is delivered. Legacy vendors like Mimecast and Barracuda have built their entire security models around rerouting your mail through their filtering engines. To get protected, you pointed your domain's MX records to them.

It made sense when environments were hybrid, fragmented, or on-prem.

But things have changed.

Microsoft 365 is now the dominant player for business email. According to Gartner's 2023 Market Guide for Email Security, Microsoft 365 accounts for over 90% of cloud-hosted business email globally. Mail flows are simpler. Direct. Centralised.

And yet we're still rerouting critical comms through third-party gateways, adding risk, delay and complexity that modern setups just don't need. Meanwhile, email remains the top attack vector - in 2024, 36% of companies experienced an email-based cyber attack, a figure that's more than doubled since 2021.

Ask any IT admin: switching email security vendors is scary mostly because of MX changes. One wrong move and everything grinds to a halt. That's not a decision - that's a hostage situation.

The reason many teams stick with "good enough"

Microsoft Defender for Microsoft 365 is underwhelming - and most teams know it. But it's native. Fast to deploy. Doesn't touch your mail flow.

So even if it misses phishing attempts, struggles with BEC, or creates a policy nightmare, it feels safer than rolling the dice on a full MX reroute.

That's why so many teams settle for "good enough". Not because it works. Because they don't want to break what's working around it.

The new standard for securing Microsoft 365 email

It doesn't have to be this way.

TrustLayer's DirectProtect Email architecture is a new connector-based mode that offers inline protection for Microsoft 365 without needing to change a single MX record. This approach builds on Microsoft's 2021 enhancements to its Graph API and mail flow connectors, which made it possible to inspect and secure email natively - no rerouting required. You stay in control of your mail flow. We handle the threats.

It installs in minutes via a five-step wizard, using Microsoft Transport Rules to apply smart filtering across inbound, outbound and internal traffic. No mail rerouting. No DNS edits. No fire drills.

Just better security. Delivered the way it should be.

When MX changes still make sense - and when they don't

Let's be honest - nobody wants to mess with MX records. They're fiddly. Risky. And just one typo away from bouncing your entire company's email into the void. But most email security providers still rely on them to get protection in place. It's been that way for years. And IT teams have just... dealt with it. But now that most organisations are deep in Microsoft 365, does that setup still make sense? Or are we all just holding onto a process that causes more stress than security? Here's a look at why MX-based email security is long overdue for retirement - and what a modern alternative actually looks like.

Questions to ask before your next email security renewal

• Why does this solution still rely on MX record changes?

• What's the rollback plan if something goes wrong?

• Can it protect internal email?

• Is it Microsoft 365-native, or just Microsoft-compatible?

• What are we actually gaining - and what are we risking?

Because if the trade-off is "more security, less stability"... it's not a great trade.

Email security should be secure - not stressful.

And it definitely shouldn't make your life harder just to do its job. There's a new standard emerging. No rerouting. No disruption. No drama. It's about time.

I recently switched to TrustLayer for our cloud security needs, and it's been a great decision. The intuitive interface and excellent support make managing our email platform for over 800 users feel effortless. TrustLayer's emphasis on complete visibility and data protection gives me peace of mind, knowing our business operates fearlessly.

Alessandro Leonardi IT Security Manager, LGH Hotel Management

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