Enter your Activation Code and the Challenge Code to generate a or use the UI to reset your license .
If you changed the network interface card (NIC), CPU, or hostname, the Challenge Code changes, making Tenable think it's a new device.
Do you have administrative access to the to reset your license? Share public link
: Find your Nessus Professional or Expert code. If it’s assigned to a host, click the "Reset" or "Manage Product > Reset Product Activation" link.
On a machine with internet access, go to the Tenable Offline Activation Page. Paste your into the first box. Paste your Reset Activation Code into the second box. Click Submit . The portal will now successfully generate two things: nessus offline activation license already in use
Copy the long alphanumeric string displayed in the terminal output. Step 3: Obtain Your New Offline License File
If you still have access to the original system where the license was first activated, this is the cleanest method.
The site will now generate a nessus.license file since the code is no longer marked as "in use". 3. Apply the License Offline
Offline activation requires a unique challenge code generated by your local machine. For Windows Systems Open the as an Administrator. Run this command to generate the code: Enter your Activation Code and the Challenge Code
A previous, half-completed activation attempt locked the license string in the Tenable cloud database. Step 1: Reset Your Activation Code (The Fastest Fix)
Solving "Nessus Offline Activation License Already in Use" Tenable Nessus is an industry-standard vulnerability scanner, but setting it up in air-gapped or strictly controlled environments requires offline activation. A common, frustrating obstacle in this process is the error.
Once the code is reset, follow these steps on your offline machine:
The "Nessus offline activation license already in use" error occurs because a Nessus activation code is restricted to a single host at a time. If you attempt to activate it on a new offline system while it is still associated with a previous installation—even one that was uninstalled—the registration will fail. Share public link : Find your Nessus Professional
A successful registration will display: "Nessus has been registered properly - thank you".
If you use virtual machine templates, never clone a VM that already has an activated copy of Nessus installed. Install Nessus after deploying and finalizing the hardware/network settings of the new VM.
The system will output a unique, one-time challenge code.
