Etabs License Not Recognized Error 120 Work May 2026

Causes of “License not recognized — Error 120” in ETABS

• License service not running: The ETABS/CADLM license manager (e.g., FlexNet/LMTOOLS or CACLS) is stopped or crashed.
• Wrong license file or host ID: License file doesn’t match the machine’s MAC/host ID or points to a different server.
• Port or firewall blocking: Required ports (usually 27000–27009 or as configured) are blocked between client and license server.
• Multiple license managers/conflicts: Two license managers installed or residual license service from older versions interfering.
• Incorrect environment variables: LICPATH.LIC, LM_LICENSE_FILE or similar variables point to the wrong file/server.
• License expired or usage exceeded: The license has expired or all seats are currently in use.
• Network name resolution issues: DNS or hosts file misconfiguration prevents client from resolving the license server name.
• Permissions issue: License files or service lack proper read/execute permissions (Windows: run service as user with rights).
• Time/date mismatch: Large clock drift between client and server can trip license validation.

2. Check the License Manager Service

On the Server machine:

• Open the ETABS Key Server application (or CSI_License_Server).
• Check if the service status says "Started." If it says "Stopped," click Start.
• If it refuses to start, check if your Firewall is blocking the port (usually port 5093 or 1947).

Fix 2: Verify the License File Path (lslicense.lic)

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. etabs license not recognized error 120 work

2. Reinstall or Replace License File

• Navigate to ETABS install folder (e.g., C:\Program Files\Computers and Structures\ETABS 20\)
• Delete any existing lservrc file
• Copy a fresh, valid lservrc file (provided by CSI or your IT admin) into the folder
• Restart ETABS

Scenario 1: You Are Using a Hardware Key (USB Dongle)

If you have a physical purple or blue USB stick plugged into your machine, follow these steps: Causes of “License not recognized — Error 120”

How to check:

1. Open Command Prompt as Administrator.
2. Run: netstat -ano | findstr :1947
3. If any process shows LISTENING, note the PID (last column).
4. Run: tasklist | findstr <PID> to identify the conflicting program.
5. Either uninstall that program or reconfigure it to use a different port.

To change the ETABS license manager port: License service not running: The ETABS/CADLM license manager

• Edit C:\Program Files (x86)\Common Files\SafeNet Sentinel\Sentinel RMS License Manager\wlmadmin\wlm.ini
• Change Port=1947 to another value (e.g., 1948), then restart the service.

3. Client-Side Configuration

On Your computer (the Client):

• Open ETABS.
• When the license error pops up, look for a "Server" or "Settings" button in the error dialog box.
• Ensure the Server Name/IP Address is typed correctly. It should match the name or IP of your company server.
• Pro Tip: If you recently changed Wi-Fi networks (e.g., switched from Office Wi-Fi to VPN or Ethernet), the IP address of the server might be different.

The Resolution Protocol

Follow these steps in order to diagnose and resolve the issue.