@Lakotaubp - No. You are going too far. You must understand the constraints I am working with. I may not be explaining these well.
The adb utility you referred me to is not installing or, executing properly. I have been trying to use v1.4.3 because, it is stated to be for Android 6+ and this is the version of Android currently on my N5. After answering "Y" to the first to questions after running the executable in Windows (Note this version of the utility only runs, it makes no attempt to install in Program Files.) I see a message stating 0 files copied. This is not correct. I attempted to install adb-setup-1.3 and this worked as desired. (4) files were copied and the installation proceeded as you see in many blogs regarding this topic. Okay. Good to go on the "15 s adb installer" yet, this should be the wrong version as Android 6+ is supposed to use v1.4.3.
Universal ADB Driver - I navigate to this via the Start menu choice for All Programs. ClockworkMod appears here and a shortcut titled "Start ADB Server" is listed under this. I have both used this shortcut to start the server and chosen not to use it. This is because UBports installer is supposed to start this.
With the N5 connected to a USB port I see "Android Device" in Device Manager. This says Google Nexus ADB Device beneath it.
On to UBports installer - I launch it, connect the N5 to the USB port when instructed to do so, N5 enters USB Debugging Mode, I choose "Select device manually" because, I have been unable to locate any setting resembling OEM Unlock in the Developer Options in my N5. Next, I select Nexus 5 from the pull down list and I am ready to install. I press "Install" and then place the N5 in Bootloader mode. Bootloader screen is displayed with this information. I think lock may still be an issue despite my recent progress.
Still, installation does not proceed. Are you suggesting I boot into Ubuntu, connect my phone to USB then execute the sudo OEM unlock then, resume trying to flash in Windows?
Edit - I just found this reference discussing unlocking the N5 bootloader.
I do not know if this is correct or definitive.
I installed SDK Tools earlier today but, I find typing "adb devices" echo's back the message, 'adb' is not recognized as an internal or external command, operable program or batch file. I have no idea how to resolve this issue but, I can tell you I have launched a command prompt window from both my "sdk-tools-windows-4333796" and "sdk-tools-windows-4333796/tools" directories and I obtain the same result.
I need to determine what is going on with SDK Tools and the v1.4.3 of the 15s adb installer.