How to Remove Ransomware from a Corporate Network Safely and Effectively
- Neil Hare-Brown
- Apr 18
- 3 min read
If your organisation’s network has been hit by ransomware, the priority is to contain the threat and prevent further damage - not just to individual machines, but to servers, shared drives, backups, and cloud environments.
This guide walks through the critical steps to remove ransomware from a corporate environment safely, while preserving evidence and avoiding mistakes that can complicate recovery.
Step 1: Isolate Infected Systems Immediately
Start by breaking the chain of infection:
Disconnect infected endpoints from the network (wired and wireless)
Disable VPNs and remote access systems
If multiple systems are affected, consider isolating entire network segments
Do not power off machines unless advised - memory may help identify the ransomware strain
The goal is to stop the spread and keep systems in a state where investigation is still possible.
Step 2: Preserve Ransomware Evidence
Before attempting removal or reimaging:
Preserve one or two infected hosts for potential forensic analysis
Save copies of ransom notes, file extensions, and encrypted files
Take screenshots of any pop-ups or Tor-based negotiation portals
Collect logs and system snapshots for forensic analysis
This information helps determine the ransomware strain, how it entered your network, and whether recovery tools exist.
Step 3: Identify the Entry Point and Infection Scope
To remove ransomware effectively, you need to understand:
How it entered (e.g. phishing, RDP, vulnerable services)
Which users, endpoints, servers, and shares were affected
Whether the ransomware is still active or has completed encryption
If data was also exfiltrated (double extortion)
A full network scan and forensic review will be necessary, ideally with expert help.
Step 4: Do Not Attempt DIY Decryption Tools Without Verification
Many free tools claim to decrypt files, but using the wrong one - or running unknown software - can cause more harm by:
Corrupting your encrypted files permanently
Triggering further malware activity
Destroying forensic evidence
Always consult a trusted cybersecurity provider before running any ransomware removal tools.
Step 5: Decide on Restoration Strategy
Option A: Recover from Clean, Isolated Backups
Restore only after confirming the network is clean
Use backups that are offline, immutable, or air-gapped
Monitor restored systems carefully
Option B: Rebuild Critical Systems from Scratch
For systems where backups aren’t trusted or available
Ensure updated OS, security patches, and endpoint protection are applied
Option C: If Decryption or Recovery Requires Negotiation
In situations where backups are unavailable and a free decryptor doesn’t exist, you may need to engage directly with the threat actor. This should never be done without expert support.
STORM Guidance provides professional ransomware negotiation services, including:
Verifying the attacker’s credibility and history
Managing communication securely and discreetly
Attempting to reduce ransom demands
Coordinating secure receipt and testing of decryptors
Ensuring compliance with legal and regulatory obligations
Every step is handled with discretion, security, and your long-term recovery in mind.
Step 6: Re-secure the Network
As part of recovery:
Reset all user and admin credentials
Apply multi-factor authentication across systems
Patch known vulnerabilities and exposed services
Review firewall rules and access controls
Implement continuous monitoring and logging
Step 7: Communicate and Report
Depending on the outcome:
Report the incident to your regulator (e.g. ICO in the UK)
Notify your cyber insurer
Inform clients, partners, or suppliers if systems were exposed or disrupted
Log actions and findings for audit and insurance purposes
Step 8: Review, Learn, and Prepare
Once recovery is underway:
Conduct a full post-incident review
Update your incident response plan
Run training and phishing simulations
Consider tabletop exercises for leadership and IT teams
How STORM Guidance Can Help
✔ Ransomware containment and secure network restoration
✔ Full forensic investigation and threat identification
✔ Regulatory support and communications guidance
✔ Ransomware negotiation strategy (if needed)
✔ Resilience reviews and recovery planning
Ransomware Can Be Removed — With the Right Steps and Support
Trying to remove ransomware alone, especially across a corporate network, can be risky.
With expert guidance, you can contain the threat, recover data safely, and navigate attacker communication if it becomes necessary.
STORM Guidance is ready to support your business — from technical containment to secure negotiation and full recovery.
