Nessus Offline Activation License Already In Use

Locate the specific Nessus activation code that is throwing the error.

When attempting a Tenable Nessus offline activation , the error "license already in use" typically indicates that your activation code is still linked to a previous installation or a different hardware ID. Because Nessus licenses are locked to a single host, you must manually release the code before it can be applied to a new offline environment. Why This Error Occurs

Offline scanners require manual plugin updates. Follow the guide at Tenable Software Updates Are you performing a fresh installation , or are you trying to an existing license to a new air-gapped machine? Update License Offline (Tenable Nessus 10.11) nessus offline activation license already in use

If you’re seeing the error during an offline activation of Nessus (Nessus Professional or Tenable.sc), it usually means the license file or challenge code is tied to a previously activated instance—even if that instance no longer exists. Here’s how to resolve it.

/opt/nessus/sbin/nessuscli fetch --register-offline nessus.license Use code with caution. Install the plugin package: /opt/nessus/sbin/nessuscli update all-2.0.tar.gz Use code with caution. Restart the service: systemctl restart nessusd Use code with caution. Best Practices to Avoid Future Lockouts Locate the specific Nessus activation code that is

Reinstalling Nessus on the same machine without first resetting the license leaves the old footprint active on Tenable’s servers.

: Only the Primary Contact or assigned Product Owner has permission to perform this reset. Why This Error Occurs Offline scanners require manual

: Access the Tenable Community Portal from an internet-connected device.

You must release the license from the old hardware signature before activating it on the new one. Navigate to the and log in. Click on My Products from the main dashboard.