Email defence is a layer of security that filters and blocks threats before they reach your team’s inbox. Over 90% of cyberattacks start with an email, whether that is a phishing link, a malicious attachment, or a fake login page.

Email defence services scan every inbound and outbound message automatically, blocking threats at the gateway before anyone in your business has the chance to click on something dangerous. Without it, your staff are the only line of defence against attacks that are specifically designed to look legitimate.

Phishing is an email designed to trick the recipient into clicking a malicious link, handing over login credentials, or transferring money. Phishing emails commonly impersonate banks, HMRC, Microsoft, suppliers, and senior colleagues. Modern phishing attacks are highly convincing and difficult to spot by eye.

Our email defence service scans every inbound message for phishing indicators, including sender impersonation, suspicious links, and domain spoofing, and blocks or quarantines suspicious messages before they reach the inbox.

Business email compromise, sometimes called BEC, is one of the fastest-growing and most financially damaging cyber threats to small businesses. It involves an attacker spoofing or hacking a senior employee’s email address, then sending a convincing request to transfer money, change supplier bank details, or share sensitive information. The email looks like it comes from someone the recipient trusts.

We protect against this by configuring sender authentication controls, specifically SPF, DKIM, and DMARC records, which make it significantly harder for attackers to impersonate your domain or your suppliers’ domains.

SPF (Sender Policy Framework), DKIM (DomainKeys Identified Mail), and DMARC (Domain-based Message Authentication, Reporting, and Conformance) are three email authentication standards that work together to verify that an email claiming to come from your domain was actually sent by you. Without them, anyone can send an email that appears to come from your address.

With them in place, receiving email servers can verify the email’s origin and reject or flag messages that fail the check. We configure all three as part of our email defence service and check them regularly as part of ongoing domain monitoring.

Yes. Every inbound email attachment is scanned automatically before it is delivered. Infected PDFs, Word documents with embedded macros, fake invoices, zip files containing ransomware, and other malicious file types are caught and quarantined before they reach your team.

We also block specific high-risk file types from being delivered at all, reducing the risk of a dangerous attachment being opened accidentally.

Outbound filtering scans emails leaving your organisation as well as those arriving. If a device on your network is compromised and starts sending malicious or spammy emails without your knowledge, outbound filtering catches it before it damages your domain’s sender reputation, gets your domain blacklisted, or spreads infection to clients and partners.

A compromised email account sending spam is also a sign of a broader security incident that needs to be investigated immediately. Outbound filtering flags this automatically.

Yes. Our email defence service integrates with Microsoft 365, including Exchange Online, and Google Workspace, including Gmail, as well as on-premise Microsoft Exchange. The security layer is configured at the platform level and works in the background without any changes needed on individual devices or by individual users.

Yes. For businesses that handle sensitive information by email, we configure email encryption so that confidential messages are protected in transit between sender and recipient. Encryption can be triggered automatically based on the content of the message, the recipient, or applied manually by the sender.

This is particularly relevant for businesses handling personal data, financial information, legal documents, or any other sensitive material that should not be readable if intercepted.

Microsoft 365 includes a baseline level of spam and malware filtering, called Microsoft Defender for Office 365, but the default settings are not sufficient on their own. The built-in filtering needs to be configured correctly to be effective, and even then it benefits from additional layers.

Our email defence service combines correct configuration of Microsoft’s native tools with additional policies covering anti-phishing, safe links, safe attachments, and sender authentication, giving you a more comprehensive and correctly enforced level of protection than default Microsoft 365 settings provide.

It significantly reduces the risk. Ransomware is frequently delivered via email, either as a malicious attachment or a link to a download. Our email defence service scans attachments, checks links, blocks dangerous file types, and quarantines suspicious messages before they reach the inbox.

No email filtering is 100% effective, which is why we combine it with endpoint protection, web-level threat blocking via DNS filtering, and automatic patching. Multiple overlapping layers of protection ensure that if something gets through one control, others are in place to catch it.

Email defence configuration and ongoing management is included for managed support clients as part of the security stack we deploy and maintain. This covers the configuration of anti-phishing, safe links, safe attachment, and outbound filtering policies within your Microsoft 365 or Google Workspace environment, as well as SPF, DKIM, and DMARC configuration for your domain.

If you require a dedicated third-party email security gateway in addition to platform-level filtering, this can be quoted as an additional service following a free site survey.

Report it immediately. In Microsoft 365, users can report suspicious emails directly using the Report Message button in Outlook, which sends it to Microsoft for analysis and helps improve filtering. You should also notify your IT support provider so they can investigate whether anyone clicked any links or attachments, check for signs of account compromise, and tighten filtering rules to prevent similar messages getting through in future.

Network Fish clients should call our helpdesk immediately if a suspected phishing email is reported by a member of staff, so we can assess and respond quickly.