10 Essential Tips to Protect Your Business from a Dangerous Inbound Email

Many businesses, especially small and medium-sized enterprises (SMEs), are increasingly vulnerable to email-based cyberattacks. Despite the growth of advanced email filtering technologies, many users continue to fall victim to age-old tricks such as fake attachments and malicious embedded links. The common advice from IT professionals is to “avoid dodgy emails” or “just filter them out,” but such vague guidance doesn’t always provide the practical steps needed to protect yourself from inbound email-based threats.

In this blog, we’ll cover 10 essential tips that can help you and your business stay safe when dealing with inbound email. These steps are simple, actionable, and can be applied by anyone, regardless of their technical expertise. By following these best practices, you can greatly reduce the risk of cyberattacks coming through your inbox.

1. Always Check the Sender

The first line of defence against malicious emails is to scrutinise who the email is from. If you’re not expecting the email, approach it with caution. Cybercriminals often use unsolicited emails as a way to capture your attention or trick you into clicking on a malicious link. Always ask yourself: Was I expecting this email?

Look closely at the email address, particularly the domain name that comes after the “@” symbol. If the domain is unfamiliar or originates from a country with which you have no business dealings—such as “.ru” for Russia or “.ne” for Nigeria—it’s wise to be suspicious. If you’re not sure, it’s better to err on the side of caution and delete the email.

Even if you recognise the name of the sender, double-check the actual email address. Cybercriminals are skilled at making emails appear as though they come from someone you know by mimicking their email address with small variations. Never let your guard down simply because the name seems familiar.

2. Examine the Subject Line

Cybercriminals often use enticing subject lines to grab your attention. Common tactics include offering fake refunds, cash prizes, or other financial rewards. These subject lines are designed to get you excited, hoping you’ll drop your guard and engage with the email. Always treat such offers with scepticism. If it seems too good to be true, it probably is.

3. Be Wary of Attachments

If the inbound email contains an attachment, and you weren’t expecting it, proceed with caution. Attachments can easily carry harmful software that can compromise your system. Malware, ransomware, and viruses are often hidden within seemingly innocent-looking files. Before you open any attachment, consider these questions: Does the attachment’s name make sense? Does it align with the content of the email? Is it unusually short or contain a random mix of letters and numbers?

If anything about the attachment feels off, don’t open it. It’s far safer to delete the email and contact the sender to verify if they meant to send it. Remember, it’s digital—it can always be sent again.

4. Analyse the Email’s Content and Tone

If you know the sender personally or professionally, ask yourself whether the tone and writing style match what you expect from them. For instance, if the sender typically uses casual language but the email appears overly formal or riddled with errors, that’s a red flag. Fraudsters often use generic or automated templates that don’t sound natural. If the writing feels out of character, take a step back and think before clicking any links or opening attachments.

5. Scrutinise Links Before Clicking

Many malicious inbound emails contain web links designed to trick you into downloading harmful files or visiting fraudulent websites. Before clicking on any link, hover your cursor over it to see the full URL. Be especially cautious if the link seems to lead to an unfamiliar or suspicious website.

For example, compare these two links:

http://www.bbc.co.uk/news/technology-36913000
http://www.bbc.so/news/technology-36913000

While they may look similar at first glance, the second link directs to a “.so” domain, which is not associated with the legitimate BBC site. Always double-check URLs before clicking, especially if the email was unexpected or contains an unusual subject line.

6. Enable and Regularly Update Your Antivirus Software

An up-to-date antivirus program acts as an essential line of defence against malicious inbound emails. Antivirus software helps detect harmful attachments, malicious links, and other threats before they can cause damage to your device. Ensure your antivirus software is set to update automatically so that it stays current with the latest security patches.

7. Use Email Filtering and Scanning Tools

Implementing a mail filtering or scanning service, like Acora One’s MailGate product, can significantly reduce the likelihood of dangerous emails reaching your inbox. These services automatically scan inbound email for known threats, block suspicious attachments, and filter out harmful URLs. By stopping malicious emails at the source, you reduce the risk of an employee accidentally clicking on a dangerous link.

8. Be Cautious with Unsolicited Emails from Foreign Domains

Emails from foreign domains, particularly those with “.ru”, “.ne”, or other high-risk country codes, are often used in phishing attempts. If you don’t have business dealings with organisations or individuals in these countries, it’s usually best to avoid opening these emails altogether. Legitimate companies typically use familiar domain names and professional email addresses.

9. Develop a Company-Wide Email Security Policy

For SMEs, it’s crucial to have a clear email security policy in place that all employees are trained on. This policy should include guidelines on how to handle unsolicited emails, what to do with suspicious attachments, and steps to follow if a malicious email is opened by accident. Regular training ensures that everyone in the company knows what to look for and how to react to potential threats.

10. When in Doubt, Contact the Sender

If you receive an email that seems suspicious but you’re unsure whether it’s legitimate, the safest option is to contact the sender directly. Use a separate method—like calling them or sending a new email to an address you already have on file. This ensures you don’t inadvertently fall victim to a phishing scam. It’s always better to verify than to risk a data breach.

Final Thoughts: Staying Safe from Inbound Email Threats

While this article encourages a cautious approach to handling inbound email, it’s important to remember that most emails are completely safe. Millions of legitimate emails are sent every day without issue. By following these practical tips, you can significantly reduce the chances of falling victim to email-based cyberattacks, while still benefiting from the efficiency and convenience of email communication.