Undeterred, John continued his investigation. He checked the system's hosts file, suspecting that maybe there was an incorrect entry blocking the license server. After analyzing the file, he found an entry that seemed suspicious. The entry was pointing to an old IP address that was no longer valid.
Follow these troubleshooting procedures in order to restore connection to the validation servers. 1. Link Your License to a Lumion Account
In Notepad, click and navigate to: C:\Windows\System32\drivers\etc\ .
Sometimes the error is a lie of omission. Log into your Lumion account via a web browser. Ensure your license has not expired. If it has, renewing it will solve the error instantly.
Press the Windows Key, type , and press Enter. Click on Outbound Rules in the left-hand sidebar. Undeterred, John continued his investigation
Fortunately, this is almost always a network configuration issue rather than a broken software installation. Here is a comprehensive guide to diagnosing and fixing the issue so you can get back to rendering. Root Causes of the Connection Failure
Locate the , Exceptions , or False Positives setting panel.
If you are on a restricted network (like an office or school), ensure your network administrator has whitelisted these requirements: : 443 (HTTPS) and 80 (HTTP). *.lumion.com *.lumion3d.net *.mylumion.com 5. Clear Startup Conflicts Run as Admin : Right-click the Lumion shortcut and select Run as administrator Force Startup CTRL + SHIFT
If you are still experiencing issues, double-check that your internet browser can successfully load standard web pages, and verify with your office IT administrator that port 443 (HTTPS) is fully open on your office router. The entry was pointing to an old IP
To prevent future blocks, add the following directories to your antivirus "Exclusions" list: The main installation folder (e.g., C:\Program Files\Lumion 12.0 The user data folder (e.g., C:\Users\[YourName]\Documents\Lumion 12.0 Lumion.exe file itself. 2. Update Your Windows Firewall
In some cases, reinstalling the software or re-authorizing the license dongle (if you're using one) can resolve the issue.
Corrupted network routing data or outdated DNS caches can prevent your computer from finding the correct path to the Lumion server.
Are you using a or a managed corporate/school network ? Link Your License to a Lumion Account In
Double-click the file named (it will not have a file extension).
Click . Ensure Windows does not append a .txt extension to the filename. 2. Configure Windows Defender Firewall
He tried to disable the network adapter and re-enable it. He flushed the DNS cache. He edited the host files with the precision of a surgeon. Nothing.