Etabs License Not Recognized Error 120 May 2026

ETABS "License Not Recognized" Error 120 typically occurs when the software cannot verify your license through the Sentinel RMS License Manager. This is usually due to an outdated license file, a blocked connection, or a service that has stopped running.

Below is a draft you can use for a technical support request or a troubleshooting guide for your team. Draft: Troubleshooting ETABS Error 120 Technical Issue: ETABS License Not Recognized (Error 120) Problem Description:

When attempting to launch ETABS, the following error message appears: "License not recognized. Error 120."

This prevents the software from opening and accessing the network or standalone license. Recommended Troubleshooting Steps: Restart the License Service: Services.msc on the license server (or local machine for standalone). Sentinel RMS License Manager Right-click and select Verify the License File: Ensure the file is present in the ETABS installation directory. Check if the license has expired. You can use the WlmAdmin.exe tool to verify the expiration date and number of users. Check Environment Variables: Ensure the system environment variable LSFORCEHOST

is set to the correct IP address or hostname of your license server. Network & Firewall Check: Confirm that UDP Port 5093 etabs license not recognized error 120

(the default for Sentinel RMS) is open and not being blocked by a firewall or antivirus software. Re-run the License Activator: In the ETABS installation folder, find and run CSiLicensing.exe LicenseRequest.exe

) as an administrator to ensure the locking code matches the current hardware. Next Steps: If the error persists after these steps, please generate a License Request File (.lic)

and send it to the IT department or CSI Support for a license renewal or re-activation. to CSI or an internal memo for your engineering team?

Step 3: Verify Your License File Location (Network Licenses)

For network licenses, ETABS needs to know where the server is. If the path is wrong, you get Error 120. ETABS "License Not Recognized" Error 120 typically occurs

  1. Navigate to the ETABS installation folder (usually C:\Program Files\Computers and Structures\ETABS 20\).
  2. Find the file named lservrc (no extension). Open it with Notepad.
  3. It should contain one of two things:
    • For Local Licenses: A long encrypted string of letters/numbers.
    • For Network Licenses: A line that says 2700@YourServerName (e.g., 2700@Engineering-PC).

Fix: Ensure the server name is spelled correctly. Try replacing the computer name with the IP address (e.g., 2700@192.168.1.10).

Solution 1: Check Antivirus and Firewall Settings (Most Common Fix)

The most frequent cause of Error 120 is Windows Security blocking the ETABS.exe file from verifying the license.

What Causes ETABS Error 120?

Before fixing the issue, it helps to understand why it happens. Error 120 usually stems from communication issues between the software and the licensing system. Common culprits include:

  1. Firewall/Antivirus Blocking: Windows Defender or third-party antivirus software is blocking the ETABS executable or the license manager from accessing the network.
  2. Corrupt License File: The local license file (usually ending in .lic) has become corrupted or is missing.
  3. Version Mismatch: You are trying to open a model created in a newer version of ETABS with an older version license, or the license file does not match the installed build.
  4. Network Issues (For Network Licenses): The client machine cannot reach the server, or the server name is incorrect.
  5. Virtual Environment Issues: Running ETABS on a Mac (via Parallels or Bootcamp) or a VPN can sometimes confuse the hardware ID checks.

Step-by-Step Troubleshooting Guide

Follow these steps in order. Start with the simplest (restarting services) and move toward more complex solutions (file editing). Step 3: Verify Your License File Location (Network

Overview

Error 120 is a common yet frustrating licensing issue that occurs when ETABS (or CSI Software) cannot communicate with the license server or local license file. It typically appears during software startup, blocking access to the program. While the error message is vague, it usually points to one of three root causes: network/server communication failure, outdated license manager tools, or corrupted license path settings.

How to Fix ETABS License Not Recognized (Error 120)

If you are an structural engineer relying on CSI software, few things are as frustrating as being ready to run a complex model, only to be stopped dead in your tracks by a licensing error.

One of the most common issues ETABS users encounter is Error 120: License Not Recognized. This error essentially means that the ETABS application cannot establish a handshake with the license server, even if you believe your license is valid.

In this guide, we will walk through the most common causes of Error 120 and provide step-by-step solutions to get your software up and running again.

Immediate checks (quick wins)