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. etabs license not recognized error 120
The most frequent cause of Error 120 is Windows Security blocking the ETABS.exe file from verifying the license.
For structural engineers, ETABS (Extended Three-dimensional Analysis of Building Systems) is the gold standard for building analysis and design. However, few things are as frustrating as sitting down to meet a deadline, launching the software, and being greeted by the dreaded "Error 120: The license is not recognized by the license server." If you are an structural engineer relying on
This error effectively locks you out of your work. It indicates a breakdown in communication between your computer (the client) and the machine holding the license (the server—either a physical computer in your office or a cloud-based license manager).
Don't panic. In 90% of cases, Error 120 is not a license revocation but a network or configuration issue. This comprehensive guide will walk you through what Error 120 means, why it happens, and—most importantly—how to fix it permanently. The most frequent cause of Error 120 is
This is the solution that resolves the issue in 90% of cases. ETABS installs a driver called the "Sentinel Protection Installer" to manage licenses. If this driver becomes corrupted or fails to update, ETABS will throw Error 120.
Steps to fix:
Once your computer restarts, launch ETABS. The license should now be recognized.
| Pros | Cons | |------|------| | Network licenses allow flexible sharing across a team. | Error 120 is cryptic and requires admin-level troubleshooting. | | Standalone (USB) option available for frequent travelers. | License Manager tools feel outdated (based on FlexNet). | | | No clear error log explaining which feature is unrecognized. |