The Bootcamp Assist tool is pretty flaky in general. When it's on the happy path it appears to make everything much easier. But the moment something goes wrong it tends to be pretty useless and can provide misleading information on what is actually going on. I've got a Power Mac, a Mac Book Pro, and an iMac. If I do a fresh install of mac OS High Sierra on any of them Boot Camp Assist tends to fail in some way or another. After much pain and frustration I've got my procedures and steps that I go through to get around the problem.
For the Boot Camp drivers once you get your hands on them you'll want to archive them somewhere. Store them in your online storage somewhere. Of course you don't already have the drives. To get them (if you are okay using development tools) you can use a script that Tom Sutton wrote called "Brigadier." To run the script do the following.
- Press the command button and the space button at the same time and then type "terminal" and press enter.
- When the Terminal window opens type the following (or copy this and past it into the terminal window)
cd ~/Desktop
md Bootcamp
cd Bootcamp
git clone https ://github.com/timsutton/brigadier
cd brigadier
./brigadier
- After the above commands have been run close the terminal window
- Open a Finder window and navigate to your Deskop
- Open the Bootcamp folder on your desktop
- open the Brigader folder inside of the Bootcamp folder
- You will see a Bootcamp folder that has the specific files needed for your installation
With all that done you are past the obstacle of getting Bootcamp. The next potential obstacle is repartitioning the disk. Sometimes at this step Bootcamp will show a progress bar that stops progressing. This can be hard to spot as when it works properly it can be slow. If you find that Bootcamp cannot repartition the disk close Bootcamp Assist and reboot your machine while holding Command, Option, P, and R. You'll hear the Mac start-up sound, but don't release the buttons. Wait until you hear it a second time and then release them. After your computer boots try again to repartition the disk.
