Look for a file named:
If the server is running but ETABS still gives Error 18, the issue is usually a blocked connection. etabs license error 18 2021
Ensure the lservrc file is present. If you have a valid license file: Look for a file named: If the server
Copy it into the main ETABS installation directory (e.g., C:\Program Files\Computers and Structures\ETABS 2021 ). Also, place a copy in the CSiLicensing subfolder. etabs license error 18 2021
If you have followed all these steps and still see Error 18, the issue may be a license feature mismatch—your license file may simply not include entitlement for ETABS 2021. In that case, contact your software provider to upgrade your license plan.