Another application may be using port 1947. Common culprits: older Autodesk software, Gemalto USB dongle drivers, or Docker containers.
If you are using a floating network license and Error 120 persists, the license server itself may be misconfigured. etabs license not recognized error 120 work
Newer ETABS versions often use digital licenses tied to a machine ID. Another application may be using port 1947
Before diving into advanced fixes, run through this quick checklist: If none of these work, proceed to the systematic fixes below
If none of these work, proceed to the systematic fixes below.