The correct conclusion is D. The FortiManager 7.6 Administrator Study Guide defines Never Installed as a state where the policy package was never created and was never imported for a managed device. That means FortiManager may already know the device itself at the device layer, but the firewall policy layer has not yet been built for that device.

The lab guide confirms this behavior directly: when you choose Import Later in the Add Device wizard, the policy package status becomes Never Installed because there is still no policy package created for the added FortiGate devices.

So this is not a revision-history issue, and it does not mean ADOM policy changes are merely waiting for first install. It means the policies still exist only on the managed device side until they are imported into a FortiManager policy package.

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