ETABS uses a file named lslicense.lic to locate the license server. If this file points to a wrong IP address or hostname, Error 120 appears.

Remember: The license server is a fragile piece of infrastructure. Treat it like a critical service – monitor it, log its errors, and document any changes. With the steps above, you should never lose billable hours to Error 120 again.

Look at the USB dongle itself. Is there a small red or green light glowing?

Go to your PC settings and set the date/number format to United States (mm/dd/yyyy) . This is a common fix for CSI software.

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