Lumion 12 Is Being Prevented From Contacting The License Server Today

Lumion requires access to specific internet addresses on certain ports to function. If you are on a restricted network, your IT department may need to whitelist the following.

If the servers are operational, the next step is to ensure your license is actually valid.

If you are managing a network via a router or external firewall, make sure your security architecture whitelists outbound connections to the specific web properties designated in the Lumion Knowledge Base . Generally, Lumion requires open access to: *.lumion3d.net *.lumion.com ⚠️ A Note on Unofficial Software Lumion requires access to specific internet addresses on

If you’ve tried all the steps above and still see the message, reach out to Lumion Support via your Customer Area. They can verify if your license is correctly registered and provide advanced network logs.

Do you have any software installed besides Windows Defender? If you are managing a network via a

Check your antivirus Protection history . If any Lumion files (like DLLs in the "channels" subfolder) were quarantined, select Restore . 3. Firewall Configuration

, this feature could propose a 24-hour "emergency lease" that activates via a temporary mobile hotspot connection if the main server is unreachable. Immediate Manual Fixes If you need to fix this right now without new features: Run as Administrator : Right-click the shortcut and select Run as administrator Firewall Exclusions : Manually add Lumion.exe to your antivirus and Windows Firewall exclusion lists. Check Your Account : Ensure your Lumion 12 license is registered on the Lumion Account page on how to manually clean your Windows hosts file to unblock the server? News - Notice for Lumion 12 and older version users Do you have any software installed besides Windows Defender

Click the Windows Start menu, type , right-click it, and select Run as administrator . In Notepad, go to File > Open .

The Lumion support team worked with SecurityGuard's developers to resolve the issue, and a few days later, an update was released that allowed Lumion 12 to communicate with the license server without any issues.