Reinstalling Firmware

Hey all. I just bought a PS4 Pro today and within 30mins of booting it up, it crashed and is now requiring a reinstallation of version 4.06 or later.

I downloaded the latest firmware from playstation.com, put it on a flash drive, and followed the prompts for reinstallation, but I either get a "Error: USB not connected" or a "This file can't be used..."

I found out that there is a full version of the firmware which I am now downloading and going to try out, but I'm wondering if someone else has had this problem and could help me get through this painful process of using a new playstation product...