RealVNC Connect is a widely used remote access software solution deployed across enterprise environments, critical infrastructure, and embedded systems. In highly secure settings—such as defense, healthcare, financial systems, and industrial control environments—servers and endpoints are frequently isolated from the public internet. This isolation, commonly referred to as an air-gapped network, prevents standard cloud-based license validation. To accommodate these environments, RealVNC provides offline licensing options.
Offline keys disable all cloud-dependent functionality. To bridge connections across different networks without the cloud, you must configure direct IP-to-IP connections, port forwarding, or a VPN tunnel. Security Best Practices for Air-Gapped Networks
For IT administrators, the command line is the preferred method: vnclicense -add Linux: sudo vnclicense -add 3. Using Group Policy (Windows)
Treat your offline key like a password. Anyone with access can license unauthorized VNC servers. realvnc offline license key
A typical offline license response file is a containing:
If you are physically at the computer running RealVNC Server:
In an offline on‑premise deployment, every connection starts with a static IP address or hostname already known to administrators, with routing configuration already in place. A RealVNC Viewer connects directly to the RealVNC Server, so remote sessions run on the same network with no cloud relay in the path. Traffic uses TCP and UDP connections over port 5900 and remains confined to internal subnets. RealVNC Connect is a widely used remote access
Because offline licenses don’t phone home, they won’t auto-renew. Set up a calendar reminder 30 days before expiry to generate new request files and obtain updated keys.
No. Each offline key is machine-specific. If you need 10 offline computers, you need 10 unique response files generated from 10 separate request files.
On the offline machine:
Unlike cloud subscriptions that auto-renew their tokens, offline keys have hard-coded expiration dates embedded within their cryptographic signature.
You cannot use the RealVNC cloud relay service to discover or connect to machines over the internet. You must connect directly using the target machine’s local IP address or Fully Qualified Domain Name (FQDN). This requires a VPN or direct network routing.
Allows for license deployment in remote industrial sites. Security Best Practices for Air-Gapped Networks For IT
Typically, RealVNC Viewer does not require a license. However, if you are using a per-user subscription model that requires licensing on the viewer side, you can apply an offline license to the using the same License Wizard method (File -> Apply offline license). Troubleshooting Offline Activation
While cloud licensing offers convenience, offline licensing offers control and security: