Locate the Nessus activation code that is giving you trouble. Look for a "Reset" or "Unlink" button next to the license.
💡 Tenable limits how many times you can reset a code manually (usually once every 24 hours). If you have exceeded this limit, you must contact Tenable Support to request a manual reset. Step 2: Generate a New Challenge Code
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. nessus offline activation license already in use
When you perform an offline activation, you generate a "Challenge Code" from your local Nessus scanner. You then provide this code and your "Activation Code" to the Tenable website to receive a license file (nessus.license).
With a reset license and a new Challenge Code, you can now generate the license file. Go to the . Enter your Activation Code (the one you just reset). Paste your New Challenge Code . Click Submit and download the nessus.license file. Copy this file to your offline machine. Step 4: Apply the License and Plugins Locate the Nessus activation code that is giving you trouble
Open your terminal and run: /opt/nessus/sbin/nessuscli fetch --challenge
After the license is accepted, remember that you will also need to manually download and install the latest plugin set ( all-2.0.tar.gz ) since the machine has no internet access to pull them automatically. Pro-Tips for Avoiding Future License Issues If you have exceeded this limit, you must
Keep a record of which Challenge Code is paired with which Activation Code, especially if you manage multiple offline scanners.
Confirm the reset. This frees the code to be paired with a new Challenge Code.
The most direct way to resolve this is to reset your license through the Tenable Support Portal or the Tenable Community site. Log in to your account. Navigate to the Products or Licenses section.