Also download via (System > Dashboard > Backup).

FortiOS 6.0.15 (latest stable for the 200D) Note: The 200D cannot run v6.4 or v7.x, but that’s where the magic begins.

You cannot "jump" directly from an old version like 5.0 to 6.0.14 without risking a configuration crash. You must follow a specific sequence.

to ensure continued protection and access to the latest FortiOS features. Router-Switch.com Firmware Features in v6.0.18

Updating the firmware on a FortiGate 200D is a straightforward process that can be accomplished through the FortiOS interface or via FortiManager for centrally managed devices. Here are the general steps: