This **2026 ransomware protection guide** covers both prevention and incident response in a systematic way. If you’ve ever wondered “what do I do if I get infected?” — this guide answers with concrete steps and evidence-based guidance.
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## What Is Ransomware? Latest Attack Methods (2025–2026 Examples)
Ransomware is **malware that encrypts files on an infected PC and demands a ransom for decryption**. Once files are encrypted, they cannot be recovered without the correct decryption key.
Japan’s Information-technology Promotion Agency (IPA) ranked ransomware as the #1 threat to organizations in its “Top 10 Information Security Threats 2026” report.
### How Ransomware Infects Individual Users
The most common infection vectors for home users are:
1. **Phishing email attachments**: Malicious Office files with macros, disguised as invoices, delivery notifications, or messages from PayPay and Amazon
2. **Fake software downloads**: Malicious installers disguised as “Adobe updates” or “game cracks”
3. **Drive-by downloads**: Simply visiting a malicious site with a vulnerable browser can trigger infection
4. **USB drives**: Plugging in a found or untrusted USB device into your PC
### Double Extortion Attacks Against SMBs
**Double extortion** has surged dramatically in 2024–2025.
– **Method**: Rather than just encrypting data, attackers first steal it and then threaten to publish it unless payment is made
– **Impact**: Even after decryption, the risk of customer data, financial records, and partner information being published remains
– **Real-world cases**: Domestic healthcare providers, manufacturers, and construction companies suffered widely reported incidents in 2025
Average ransom demands against Japanese SMBs range from several million to tens of millions of yen (National Police Agency, 2025). In roughly 30–40% of cases, files are not decrypted even after payment (Coveware 2024 Report).
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## Preventive Measures to Take Right Now
### The 3-2-1 Backup Rule (Step-by-Step Setup)
**Backup is the single most important ransomware defense.** The 3-2-1 rule means:
– **3**: Keep 3 copies of your data (original + 2 backups)
– **2**: Store copies on 2 different media types (e.g., PC + external HDD)
– **1**: Keep 1 copy offsite (cloud storage or a physically separate location)
**Step-by-step setup (Windows)**
“`
1. Connect your external HDD
2. Go to Control Panel → System and Security → Backup and Restore (Windows 7)
3. Click “Set up backup” → select your external HDD
4. Schedule: set for every Sunday night
5. After backup completes, always disconnect the external HDD
(leaving it connected means ransomware can encrypt it too)
“`
**Important**: If your backup device is always connected, ransomware will encrypt your backups too. **Always disconnect after backup.**
### Keep Windows and Software Updated
Keeping software up to date is the most effective defense against ransomware that exploits known vulnerabilities.
– **Windows Update**: Settings → Windows Update → Advanced Options → turn on “Get updates as soon as they’re available”
– **Office updates**: File → Account → Update Options → Update Now
– **Browser**: Verify that Chrome and Firefox are set to auto-update
– **Adobe Acrobat / Flash (recommend disabling)**: Disable or remove unused plugins
### Ransomware Protection Features: Security Software Comparison
When choosing security software, check for ransomware-specific protection features and their quality. For a detailed buying guide, see [How to Choose Security Software](/security-software-buyout-comparison).
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## Security Software Ransomware Protection Comparison
### ESET — Machine Learning Behavioral Detection
ESET uses a combination of **HIPS (Host-based Intrusion Prevention System)** and machine learning for behavioral detection. Even without a known ransomware signature, it can detect and block behavior like “attempting to encrypt a large number of files at once.”
As covered in [Windows Defender vs. ESET](/windows-defender-eset), ESET’s behavioral engine is recognized for responding faster to new ransomware variants than Defender.
**Key features**:
– LiveGuard (cloud sandbox analysis)
– Ransomware Shield (folder protection)
– Network Attack Protection
### Norton（ノートン） 360 — Ransomware Protection + 25 GB Cloud Backup
Norton 360’s standout feature is its **built-in 25 GB cloud backup**. If your PC is encrypted, you can restore files from Norton’s managed cloud backup.
**Key features**:
– Ransomware Protection (machine learning-based)
– 25 GB cloud backup (automatic, scheduled)
– Dark Web Monitoring (credential breach alerts)
– Safecam (unauthorized webcam access detection)
### Virus Buster (Trend Micro) — Folder Protection
Virus Buster’s **Folder Shield** feature blocks unauthorized file changes in designated folders. By adding important document folders to the protected list, you can prevent ransomware from encrypting them.
**Key features**:
– Folder Shield
– AI-driven threat detection
– Pay-guard detection (unauthorized process blocking)
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## What to Do After Infection
### First Steps: Network Disconnection and Power Off
If you suspect a ransomware infection, **your actions in the first 10 seconds** determine the scale of damage.
**Do this immediately (in order)**:
1. **Unplug the LAN cable / turn off Wi-Fi** — prevent spread to other PCs
2. **Restart or shut down your router** — cut off the entire network
3. **Force-shut down the PC** — stop further encryption
4. **Check all connected external drives and USBs** — storage connected before disconnection may also be infected
**Do NOT**:
– Contact anyone listed in the ransom note
– Pay the ransom (consult a professional first)
– Open or move files on the infected PC
### Should You Pay? Cases Where Payment Didn’t Work
**Short answer: We do not recommend paying.**
Reasons:
1. **No guarantee of decryption**: Approximately 30–40% of ransomware victims who pay receive no decryption key (Coveware 2024 Report)
2. **Repeat targeting**: Companies that pay are flagged as willing payers and are more likely to be attacked again
3. **Funding criminal activity**: Your payment funds future attacks
4. **Legal risk**: Payments to sanctioned organizations (such as certain Russian criminal groups) may violate sanctions law
### Finding Free Decryption Tools (No More Ransom)
**The No More Ransom project (nomoreransom.org)** is a free decryption tool repository run jointly by Europol, Interpol, law enforcement agencies, and security companies.
**How to use**:
1. Visit `nomoreransom.org`
2. Use the “Crypto Sheriff” tool to identify your ransomware variant
3. If a free decryption tool exists for your variant, download it for free
As of April 2026, free decryption tools are available for over 180 ransomware variants (No More Ransom project). Check here first.
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## Backup Configuration: Step-by-Step
### The Limits of Windows Built-In Backup (OneDrive and File History)
OneDrive **syncs with your PC**, which means if your PC is infected, OneDrive may overwrite your cloud files with encrypted versions.
– **OneDrive version history**: You can restore files from up to 30 days ago (both Personal and Business). However, if ransomware was quietly active for months before triggering, this window may be too short.
– **Windows File History**: Backs up to a connected external HDD on a schedule. If the HDD is always connected, it’s at risk of simultaneous infection.
### External HDD + Cloud: Combined Setup
**Recommended configuration (3-2-1 rule in practice)**:
“`
[Your PC] ←→ [External HDD (weekly backup, then disconnect)]
↕
[Cloud Backup (automatic, continuous)]
– Backblaze: ~$9/month, unlimited backup
– Or Norton 360’s included 25 GB cloud backup
“`
**External HDD setup (Windows 11)**:
1. Connect your external HDD
2. Settings → System → Storage → Advanced storage settings → Backup options
3. “Select drive” → choose your external HDD
4. Backup frequency: hourly or daily
5. After backup, disconnect via “Safely Remove Hardware” in the taskbar
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## Summary: Ransomware Protection Checklist
### Before Infection (Prevention)
– [ ] **Backup (3-2-1 rule)**: External HDD + cloud double backup; disconnect after backup
– [ ] **Keep Windows and software up to date**: Enable automatic updates
– [ ] **Install security software**: Choose from ESET, Norton 360, or Virus Buster
– [ ] **Never open suspicious email attachments**: Verify sender; disable macros
– [ ] **Disable RDP or use a strong password**: Disable if not needed for work
– [ ] **Add critical folders to folder protection** (if using Virus Buster)
### After Infection (Response)
– [ ] Immediately disconnect from the network
– [ ] Shut down the PC
– [ ] Check nomoreransom.org for a free decryption tool
– [ ] Contact IPA or your security vendor’s emergency response line
– [ ] Do not pay the ransom (consult a professional first)
– [ ] File a report with the police (Cybercrime Consultation Desk)
For more on cost planning, see [Security Software Costs for SMBs](/smb-security-software-cost).
**References**
– IPA Ransomware Response Page: https://www.ipa.go.jp/security/anshin/attention/2021/mgdayori20210901.html
– No More Ransom (free decryption tools): https://www.nomoreransom.org/en/index.html
– National Police Agency — Cybercrime Countermeasures: https://www.npa.go.jp/cyber/
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