New R7450 AC2600

No error. I opened chat support feed and the person answering made that statement that we needed internet to configure the router. Sent a lot of instructions that supported that theory. Admittedly an internet connection would make it a little easier but, not having one doesn’t mean it can’t be done. I retired a few years back as a network engineer from HP. I’ve configured a lot of commercial grade routers and switches and, like you, I prefer to pre-configure then drop it in with little or no surprises. I got it going after getting my PC to set the router as my default gateway and observing how certain panels responded when moving around inside the router after restoring the firmware manually. Firmware was suspected to be corrupted. Thanks.