Antivirus or EDR: Which One Actually Protects Your Computers in 2026?

Your business has antivirus on every computer and you believe you are covered. That is what most owners in Trois-Rivières and the Mauricie believe too, right up to the day an employee clicks the wrong attachment and the entire network gets encrypted by ransomware. The antivirus was up to date. It never saw it coming.

The problem is not your software, it is the category of tool. Modern attacks no longer look like the classic virus an antivirus recognizes. That is exactly where EDR comes in. Here, without needless jargon, is the real difference between antivirus and EDR, and how to decide what your company’s computers actually need.

1. Traditional antivirus: what it does, and what it no longer does

Antivirus works on a simple idea: it compares the files on your computer against a database of known threat signatures. If a file matches a catalogued virus, it blocks it. That approach worked very well for 20 years, back when threats were identifiable files that spread slowly.

The problem is that attackers changed their methods. Today, a large share of attacks use no detectable malicious file at all. They run through tools already present in Windows (PowerShell, legitimate scripts), through stolen credentials, or through malware modified thousands of times a day to slip past signatures. Antivirus, meanwhile, is still waiting to recognize something it already knows.

What antivirus still does well:

• Blocking viruses and malware that are already known and catalogued
• Protecting against unsophisticated mass-market threats
• Acting as an automatic first layer that costs little in system resources

What it does not do: spot a new attack, understand abnormal behaviour, or tell you what actually happened after an intrusion. For that you need a different kind of tool.

2. EDR: watching behaviour, not just files

EDR stands for endpoint detection and response. Instead of looking for known viruses, EDR observes what the computers are doing in real time: which programs launch, which network connections open, which files are being modified en masse, which account is trying to reach what.

When behaviour steps outside the normal range, for instance a process encrypting hundreds of files at once or an account signing in at 3 a.m. from abroad, EDR raises an alert, documents the whole chain of events and can automatically isolate the affected computer from the rest of the network. That last point is what saves a small business: you cut the spread before it reaches the file server or the backups.

EDR’s other strength is traceability. After an incident, you know exactly how the attacker got in, what they touched and how long they stayed. With plain antivirus, that information simply does not exist, which makes the incident reporting required by Quebec’s Law 25 far harder to complete.

3. Antivirus or EDR: the real differences

To decide between the two, here is what actually changes day to day:

• Detection method: antivirus recognizes known threats, EDR analyzes suspicious behaviour, including behaviour nobody has seen before.
• When it acts: antivirus blocks at the door, EDR watches continuously and reacts even after an intrusion.
• Response: antivirus deletes a file, EDR isolates a computer, kills a process and reconstructs the whole attack.
• Visibility: antivirus gives you an alert, EDR gives you a complete investigation you can use for compliance.
• Target: antivirus aims at mass-market threats, EDR aims at targeted attacks and modern ransomware.

The good news is that this is not really an either-or choice. Most modern EDR products already include a next-generation antivirus engine. Choosing EDR means keeping the best of antivirus and adding the layer that was missing. If you want a clear picture of your current level of protection, an audit of your IT services is the logical starting point.

4. Why businesses in Trois-Rivières and the Mauricie get targeted

Plenty of owners still think cyberattacks only go after large Montreal companies or multinationals. What we see in the field is the opposite. Regional businesses have become prime targets precisely because they are seen as less protected, while still holding sensitive data and being able to pay a ransom.

The Canadian Centre for Cyber Security notes that ransomware ranks among the most likely and most damaging threats to Canadian organizations. A manufacturing or service business in the Mauricie that loses access to its files for a week is facing an immediate production crisis.

On top of that sits Law 25 on the protection of personal information, which requires Quebec organizations to report privacy incidents that present a serious risk. Without EDR, proving what was and was not touched during a breach becomes nearly impossible, which weakens both your legal position and your insurance file.

5. Managed EDR: the realistic option for a small business

EDR generates a lot of alerts, and that is normal: it sees everything. But an alert nobody reviews in time is worth nothing. Most smaller companies do not have a security analyst on hand around the clock to sort through those signals. That is where managed EDR, also called MDR (managed detection and response), comes in.

In practice, your IT partner deploys the EDR, monitors alerts continuously, sorts real incidents from false positives, and steps in on your behalf when a threat is confirmed. You keep the protection without having to build a security team in house.

• Continuous monitoring of workstations and servers, day and night
• Human triage of alerts to avoid fatigue and blind spots
• Fast response: isolate the computer, stop the attack, clean up
• Clear reports for management and for your Law 25 obligations

For a business in the region, that model usually makes the most sense: enterprise-grade technology, operated by an outside team that knows your environment.

6. How to choose and deploy without missteps

Before you replace or supplement your antivirus, take the time to frame the project. Here is a simple approach:

• Take inventory: how many workstations, servers and mobile devices, and which systems (Windows, Mac, Microsoft 365) need protection.
• Identify your sensitive data: client files, financial records, personal information covered by Law 25.
• Check compatibility: a good EDR integrates with Microsoft 365 and Microsoft Defender so email and identity are covered too.
• Choose the managed route: unless you have a dedicated security team, pick an EDR monitored by your IT provider.
• Plan the rollout: gradual installation, testing, and a short training session so employees know the right reflexes.

The goal is not to pile up software, it is to have protection that is coherent, monitored and aligned with your real risks. A local partner can do that framing work with you in a few meetings.

Frequently asked questions

Does EDR completely replace antivirus?

In practice, yes. Modern EDR products include a next-generation antivirus engine, so you do not need to keep a separate antivirus: EDR covers both functions and adds behavioural monitoring.

Does a 10-employee company really need EDR?

Yes. Size is no longer a criterion for attackers, who go after the least protected organizations. A 10-person business holding client data has as much reason to protect itself as a larger one, especially with Law 25 requirements in Quebec.

Can you install EDR yourself?

Technically the installation is doable, but the effectiveness depends on someone watching the alerts continuously. With nobody to analyze and respond, the tool loses most of its value. That is why EDR managed by an IT partner is the recommendation for most smaller businesses.

Protect your computers with an IT partner from the Mauricie

Moving from antivirus to EDR does not have to be complicated. At OKTO Solutions, we help businesses in Trois-Rivières, the Mauricie and elsewhere in Quebec assess their real level of protection, deploy managed EDR and stay compliant with Law 25. Take a look at our managed IT services or write to us through our contact page for a first conversation with no obligation.

Complete guide: Law 25 for Quebec businesses
The obligations by deadline, the official sources, the fines the law provides for and the common questions, on a single page kept up to date.