Need help unlocking my Nexus 7 2012 to downlevel the OS

[Moondoggy]

I'm looking for some help back leveling my Nexus 7 from version 5.1.1 to 4.4.4 as I've hit a roadblock and can't figure out what I need to do next.

I downloaded and installed the Android tookkit, and the required java toolkit.
I downloaded the 4.4.4 version Nakasi for Nexus 7 wifi OS files
I was able to plug my Nexus into my PC and my PC recognized it as a Nexus 7 under portable Portable device in Device Manager
I successfully went into settings on my Nexus 7 and set it up for debugging and authorized it for my PC
I was able to run ADB DEVICES command and it successfully found my device
I was able to run the ADB REBOOT BOOTLOADER command and my Nexus showed the Bootloader settings and it said that the device was locked.
According to the instructions I have the next command I'm supposed to run with the Nexus connected to my PC is FASTBOOT OEM UNLOCK. but when I execute this command the program displays < waiting for any device >.and all it does is patiently wait but nothing happens. I have left the device plugged in and nothing happens and I tried restarted the bootloader from my nexus and nothing happens
I subsequently downloaded the Nexus Root Toolkit v2.1.5 and installed it and when I attempt to unlock the device from that tool it indicated that it cannot find the device to unlock.

So, at this point, I don't know what is going wrong and what I need to do to get the PC to recognize the device once it's in Bootloader mode. Can anyone help me?

 

[Moondoggy]

Well, after reading many additional articles on the internet I finally ran across the problem and solution. It seems that in Windows 10 the system recognizes the device when it's plugged in and turned on in normal mode but once you run the command to switch it into bootloader mode Windows 10 no longer sees that device it sees it as a ADB device and Windows 10 didn't have a device driver installed for it. It was suggested that I go to [TOOL] [WINDOWS] ADB, Fastboot and Drivers -… | Android Development and Hacking and download the 15 second ABD installer and run it as instructed. After I did that everything worked great and I was able to back level my Nexus 7 back to 4.4.4