# 127.0.0.1 license.lumion3d.com

Lumion 2023 moved to a subscription model. If you have a legitimate subscription and still see this, a third-party "optimizer" or firewall might have altered your hosts file without your knowledge.

Look for any lines containing the word . These typically look like: 127.0.0.1 backup.lumion3d.net 127.0.0.1 license.lumion3d.net

A: No. Windows and macOS require the hosts file for essential localhost mapping. Deleting it can break network services. Only remove the Lumion-specific lines.

Are you using an or a perpetual license , and did this error appear immediately after a recent Windows update? How do you resolve antivirus and firewall problems?