: Reinstalling the OS or deleting a Nessus instance without first deactivating the license leaves the code "locked" to the old instance. Hostname Changes
: C:\Program Files\Tenable\Nessus\nessuscli.exe fetch --deactivate . 3. Restart the Offline Activation Process nessus offline activation license already in use
Diagnostic checklist (deep)
The "License already in use" error typically occurs when Nessus detects that the license file has already been activated on another system or scanner. This error can be caused by: : Reinstalling the OS or deleting a Nessus
Confirm the reset. Once complete, the code will show as available and can be used for a new registration. : Click the Reset Product Activation link
: Click the Reset Product Activation link. Confirm the action when prompted. This "unlinks" the code from any previous host, making it available for a fresh offline registration. Step 2: Generate a New Challenge Code