| Cause | Solution | |-------|----------| | Wrong license server address | Re-enter server name or IP in ETABS License Manager. | | Firewall blocking | Add ETABS and CSI license manager executables to firewall exceptions. | | License file corrupted | Stop license manager, replace .lic file, restart manager. | | VPN interference | Use the VPN's local IP, or disconnect VPN for license check-out. | | Old license manager version | Download and install the latest CSI License Manager (compatible with ETABS 2021). |
Ensure the ls host environment variable is correctly set to your server's name. etabs license error 18 2021