Confirm the reset. This frees the code to be paired with a new Challenge Code.
The error occurs because Tenable's license server believes the code is currently active on another machine. Common causes include: nessus offline activation license already in use
Moving a Nessus VM to a new host often changes the hardware UUID, triggering a license mismatch. Step 1: Reset the Activation Code Confirm the reset
Locate the Nessus activation code that is giving you trouble. Look for a "Reset" or "Unlink" button next to the license. nessus offline activation license already in use
Open an Administrator Command Prompt and run: C:\Program Files\Tenable\Nessus\nessuscli.exe fetch --challenge Keep this new string of characters handy for the next step. Step 3: Perform the Offline Activation Again