Lumion 12 Is Being Prevented From Contacting The License Server |work| Jun 2026

If you are operating on an enterprise, university, or corporate network environment, your network administrator must configure the router or proxy server to accept outbound traffic targeted at Lumion’s networks.

A less common but significant cause involves the Windows hosts file, which can redirect Lumion's license server requests to invalid locations. This typically occurs from:

Press the , type Firewall , and select Windows Defender Firewall .

If you are a Lumion 12 user, you might have recently encountered a frustrating roadblock: a popup stating, If you are operating on an enterprise, university,

Change the file type filter (bottom right) from .txt to . Open the file named hosts .

If you use a third-party antivirus software (like Bitdefender, Norton, McAfee, etc.), consult its help documentation for how to add the Lumion installation folder and Lumion.exe as an exception in its firewall and real-time scanning modules.

Your network firewall might be actively blocking Lumion 12 from accessing the internet. You need to create an exception rule. If you are a Lumion 12 user, you

Choose on the Action screen and click Next .

If you are working in a corporate office, your company’s internal network may be preventing the handshake.

Save the file (ensure it does not have a .txt extension) and restart Lumion. 3. Configure Antivirus and Firewall Exclusions Your network firewall might be actively blocking Lumion

Once you have fixed the error, take these three steps to ensure it never returns:

Are you experiencing issues with Lumion 12 being prevented from contacting the license server? This write-up provides a step-by-step guide to help you troubleshoot and potentially resolve the issue.

If connectivity persists as an issue, the software environment may be unstable: How do you resolve antivirus and firewall problems?