Transfer the nessus.license file to your offline machine via USB or secure transfer.
The Nessus offline activation process failed because the activation/license is already in use on another scanner or another activation ID has been previously applied. This document explains likely causes, how to verify, and step-by-step remediation options (preserving scans and configuration where possible).
You might think you have deactivated a license, but the process may not have completed successfully. A forgotten active registration on an old virtual machine or a recycled test server can hold the license and prevent its reuse.
Download the nessus.license file and the plugin compressed TAR file. 4. Apply the license offline
C:\Program Files\Tenable\Nessus\nessuscli.exe fetch --challenge macOS: /Library/Nessus/run/sbin/nessuscli fetch --challenge Copy the alphanumeric string provided. 3. Obtain the license file nessus offline activation license already in use
I can provide the exact terminal paths and scripts optimized for your environment.
Virtual machine deployments often change hardware signatures if the MAC address pool fluctuates. Assign static MAC addresses to your offline scanning VMs to ensure the challenge code remains identical across system reboots or snapshot restorations. To help troubleshoot further, let me know: What Operating System is your offline scanner running on?
Keep a record of which Challenge Code is paired with which Activation Code, especially if you manage multiple offline scanners.
If you have completed these steps and still cannot activate your software, please share: Your The operating system hosting the scanner Transfer the nessus
You must manually release the license through the Tenable Support Portal or Community site. Tenable Community Support Portal My Products (usually in the upper right corner). your Nessus Professional or Expert product in the list. Select "Reset Product Activation" or click the option next to the specific activation code.
Find the specific for your OS (Linux, Windows, or macOS). Troubleshoot plugin update errors. Explain how to automate this for multiple offline scanners. Let me know which operating system you are running! Share public link
The fastest and most reliable way to clear the error is by manually resetting your activation code through your Tenable account.
: Provide the new Challenge Code and the Activation Code you just reset. You might think you have deactivated a license,
Troubleshooting the "Nessus Offline Activation License Already in Use" Error
: There is typically a limit on how frequently you can reset an activation code yourself via the portal. If you exceed this limit, you must contact Tenable Support for assistance. Update License Offline (Tenable Nessus 10.11)
To fix the error, you must clear the active license binding from the Tenable Community Portal before generating a new offline license file. Step 1: Reset the Activation Code
Modifying virtual machine hardware triggers a new challenge code.
| | Description | | :--- | :--- | | Activation Code vs. License | Activation codes are used for online activation (the scanner communicates directly with Tenable). In offline mode, the activation code is used to generate a specific .license file that is then imported into the scanner. | | Unique Challenge Code | When initiating offline activation, a challenge code is generated. This code acts as a unique identifier for that specific scanner instance and is used, alongside the activation code, to generate a bound license file. | | One License Per Instance | A single activation code can only be active on one scanner at a time. If you try to use the same code on a different machine (or even a reinstalled machine) without proper deactivation, the error occurs. |
Workarounds and safe practices when contact is delayed or impossible