Troubleshooting Tip: 'Duplicate license has been detected'

[Deepak_Girimaji_FTNT]

Description	This article describes the 'duplicate license has been detected' error that occurs when a license (.lic) file that has been previously used is being re-used on a different VM instance and offers a solution.
Scope	FortiWeb and FortiMail VM.
Solution	To resolve this condition, the VM instance where the license was previously used needs to be shut down completely for at least 90 minutes. After a 90-minute period, the VM license de-registers from FortiGuard servers and it will be possible to use it again on a new VM. Note: This is an automatic process. It is not possible to speed it up.