How to Detect and Remove Ransomware

Imagine turning on your computer and discovering that all your files are locked—and a chilling message demands payment to get them back. That’s ransomware in action, and it’s one of the most terrifying and costly forms of cyberattack today.

In 2024 alone, global ransomware damages exceeded $30 billion, with attackers targeting everyone from small businesses to hospitals, schools, and individuals. Whether you’re a home user or running a company, knowing how to detect and remove ransomware is critical.

This guide covers:

• What ransomware is and how it works

• Signs your system is infected

• What to do immediately after an attack

• How to safely remove ransomware

• Tools you can use

• How to prevent future infections

What Is Ransomware?

Ransomware is malicious software that encrypts your files or locks you out of your system. The attacker then demands a ransom—usually in cryptocurrency—in exchange for the decryption key.

Ransomware comes in various forms:

Type of Ransomware	Behavior
Crypto Ransomware	Encrypts files and demands payment for the decryption key
Locker Ransomware	Locks you out of your device entirely
Scareware	Pretends to be ransomware with fake alerts
Double Extortion	Steals data first, then encrypts and threatens to leak it online

Most ransomware is distributed through phishing emails, malicious attachments, fake software updates, or infected websites.

Common Ways Ransomware Infects Systems

📧 1. Phishing Emails

Malicious links or attachments disguised as invoices, resumes, or official documents.

🌐 2. Compromised Websites

Visiting infected sites—often disguised as downloads or flash updates—can install ransomware automatically.

💾 3. Software Vulnerabilities

Unpatched systems or outdated software are easy targets for ransomware delivery.

📂 4. Malicious Ads (Malvertising)

Even legitimate websites can display ads that redirect users to ransomware-laden pages.

How to Detect Ransomware Early

While some ransomware makes itself known immediately, others operate silently until damage is done. Here are signs to watch for:

🚩 1. Unusual File Extensions

Your files suddenly have strange extensions like .locked, .crypt, .darkside, or .zepto.

🚩 2. Slow System Performance

Ransomware encrypting files in the background can slow your device down significantly.

🚩 3. Missing or Inaccessible Files

You may get error messages like “This file cannot be opened” or “Access denied.”

🚩 4. Unexpected Pop-Ups

You receive warnings or messages claiming your system has been compromised.

🚩 5. Demand for Payment

Most clearly, you’ll see a ransom note either as a text file, browser pop-up, or full-screen message. It might read:

“Your files have been encrypted. Pay 1.5 Bitcoin to this address within 72 hours, or your data will be lost forever.”

What to Do Immediately After a Ransomware Infection

⛔ DO NOT PAY THE RANSOM

Paying the attacker:

• Does NOT guarantee you’ll get your files back

• Funds criminal activity

• May make you a repeat target

📴 1. Disconnect from the Internet

Unplug your computer from the network or turn off Wi-Fi. This prevents the ransomware from:

• Spreading to other devices

• Uploading stolen data

• Communicating with the attacker’s server

🛑 2. Isolate the Infected System

Remove the infected device from any shared networks or cloud storage accounts like Google Drive or OneDrive.

📸 3. Take Screenshots

Document ransom notes, file extensions, and unusual behaviors. This can help with forensic analysis later.

🧪 4. Identify the Ransomware Strain

Use online tools like:

• ID Ransomware

• No More Ransom

Upload a ransom note or encrypted file to help identify which ransomware you're dealing with.

How to Remove Ransomware

There are two parts: removing the malicious software and restoring your data.

🔧 Step 1: Boot Into Safe Mode

• Windows: Press F8 or Shift + Restart to enter Safe Mode with Networking.

• Mac: Restart and hold the Shift key.

Safe Mode helps prevent ransomware from running during startup.

🔍 Step 2: Run Anti-Malware Scans

Use trusted antivirus and anti-malware tools:

• Malwarebytes

• Bitdefender Rescue Disk

• Kaspersky Virus Removal Tool

• ESET Online Scanner

Run a full scan, not just a quick one. Let the tool quarantine or remove any ransomware executables found.

💾 Step 3: Restore from Backup (If Available)

If you have an offline or cloud backup from before the infection:

• Wipe the infected system

• Reinstall your OS

• Restore files from the backup

• Ensure no malware remains before reconnecting to the network

Note: Never restore from a backup that's connected during the infection—it may be compromised too.

🧩 Step 4: Use Decryption Tools (If Available)

Some ransomware strains have free decryption tools:

• NoMoreRansom.org Decryption Tools

• Avast, Emsisoft, and Kaspersky often offer unlockers for older ransomware types

If a decryptor is available for your ransomware strain, follow instructions carefully.

🔁 Step 5: Reinstall Your Operating System (If Necessary)

If ransomware is persistent or you’re unsure if all traces are gone:

• Wipe the hard drive

• Reinstall the operating system

• Apply all patches and updates

• Restore clean files only

Preventing Ransomware: Long-Term Strategies

🔐 1. Back Up Regularly

Use 3-2-1 backup strategy:

• 3 copies of your data

• 2 different media (cloud + external drive)

• 1 kept offline

Backups are your best protection against ransomware.

🧰 2. Use Strong Antivirus and Anti-Ransomware Tools

Look for software with:

• Real-time threat detection

• Behavioral analysis

• Ransomware rollback features

Top-rated options include:

• Bitdefender Total Security

• Malwarebytes Premium

• Norton 360 with LifeLock

(Affiliate links available upon request.)

📤 3. Don’t Click Suspicious Emails or Links

Train yourself and your employees to:

• Never open unexpected attachments

• Hover over links before clicking

• Verify emails from known contacts

🛑 4. Keep Software Updated

Unpatched systems are the #1 way ransomware gains access. Always:

• Update your OS

• Update browsers

• Patch third-party apps like Adobe Reader or Zoom

👨‍🏫 5. Enable Email Filters and Firewalls

Set up:

• Spam filters

• Attachment blocking rules

• DNS firewalls like Cloudflare Gateway

🧑‍💼 6. Use Least Privilege Access

Restrict admin privileges. Employees should only have access to files they absolutely need.

If You’re a Business, Develop a Ransomware Response Plan

Every minute counts. Your plan should include:

• Incident response team contact info

• List of critical assets

• Backup recovery steps

• External contacts (cybersecurity firms, legal, insurance)

• Communication protocol (internal + customers)

Final Thoughts: Ransomware Isn’t Going Away—But You Can Fight Back

Ransomware is brutal, but it’s not unbeatable. The key to survival is preparation—not panic. By practicing good cyber hygiene, maintaining regular backups, and learning to spot red flags, you can recover from an attack—or better yet, avoid one entirely.

If you’ve already been hit, act fast, isolate the infection, and seek help.