: For business-critical networks, stage the update in a non-production test environment first. This allows you to validate the upgrade process and test new features without risking your live network. A virtual machine (VM) or spare hardware is ideal for this step.

What is the device running, and what is your target version ?

Under the tab, you will see available upgrade paths.

Click and verify the file's MD5 checksum against the portal's listed checksum to ensure file integrity. Method B: Downloading Directly via the FortiGate GUI

Official firmware must be sourced directly from the Fortinet Support Portal. Log in to the Fortinet Support Portal with your credentials. Navigate to Support > Downloads > Firmware Images under the product list.

Do not skip this step. Fortinet firmware must follow a specific sequence. Upgrading directly from an old version to the latest version can corrupt your configuration file.

How to Download and Install FortiGate Firmware: A Complete Guide

Once the upgrade is complete, perform the following checks:

Keep a copy of the currently installed firmware in case you need to revert. You can download it from the same portal where you will obtain the new firmware.