Because offline licenses are manually tied to a unique hardware fingerprint, any change in your system configuration or a previous failed installation can block a new activation attempt.
/opt/nessus/sbin/nessuscli fetch --register-offline nessus.license
nessuscli.exe fetch --register-offline nessus.license nessus offline activation license already in use
On your offline scanner, apply the license using the command line:
Open your terminal and run: /opt/nessus/sbin/nessuscli fetch --challenge Because offline licenses are manually tied to a
The error occurs because Tenable's license server believes the code is currently active on another machine. Common causes include:
Once the license is reset on the Tenable side, you need to get a fresh Challenge Code from your offline scanner to ensure you aren't using cached, stale data. Locate the Nessus activation code that is giving you trouble
Locate the Nessus activation code that is giving you trouble. Look for a "Reset" or "Unlink" button next to the license.