Installing Windows 8 on an External SSD Guide

Part 2

The Upgrade Guide

The tl;dr version:

Do use a DVD to install Windows 8 (either a retail disk or a burned upgrade ISO)
Don't use a USB drive or SD card to install Windows (this causes a lot of problems; see below)
Do use Boot Camp Assistant to download the latest Boot Camp drivers (to a spare USB drive or SD card etc.)
Don't use Boot Camp Assistant to install Windows 8 (at the time of writing, it won't recognize external drives)
Do make an internal partition for the Windows 8 boot files (otherwise Windows might refuse to install)
Do read this post if you're using a USB 3 drive (the below instructions are intended for Thunderbolt drives)

A. Prepare Your Mac

If you wish to change your Mac's internal drive, now is the time.

In theory, if you already have Windows 7 installed, it will continue to work (although after you install a Windows 8 upgrade, I think the EULA prohibits the continued use of the original copy of Windows 7).

To resize, create or remove any existing partitions, just use Disk Utility from your Mac. If you want a completely fresh start, boot holding Command + R to access the Recovery System. From there you can use Disk Utility and also have the option of reinstalling OS X etc.

(If you also want to perform a clean install of Mountain Lion beforehand, OS X Daily has a helpful guide).

Update: It seems you must have an NTFS partition on your Mac in order for everything to work smoothly. It doesn't have to be large, 20MB should be enough to hold the Windows boot manager, but in the end you'll be left with something like the following:

Internal drive (excluding recovery partitions etc.):

OS X partition
Windows boot manager partition

External drive

Windows 'proper' partition

You can use OS X's Disk Utility to create a new partition for the Windows boot manager, but by default it won't be formatted NTFS. That's fine, just make a new FAT32 partition, then later you can use the Windows 8 installer to reformat this as NTFS.

Disk Utility also enforces minimum partition sizes, so you might not be able to create a sub-1GB partition. In this case, you can either:

Make a large partition and use it for storing files. Both OS X and Windows can read NTFS drives, so this partition might be handy for sharing files like photos and music etc. between both OSs (Windows of course can write to NTFS drives, and there are cheap/free NTFS write drivers available for OS X too). Or ...
Use a third-party program or some Terminal magic to create a small partition just big enough for the Windows boot manager and nothing else.

B. Prepare Windows

If you'll be using a retail Windows 8 disk, then skip ahead to Section C. However, if you'll be upgrading an existing Windows 7 installation, then continue reading.

The following instructions should work for XP and Vista, but I'll assume you're already running Windows 7.

If you already have Windows 7 installed on your Mac, first backup all your important data and settings to an external drive (other than the SSD you'll be using for Windows 8, of course). You can use Windows Easy Transfer, or just download the free version of CrashPlan to back everything up.

The easiest way to buy Windows 8 is to purchase the upgrade online from an existing Windows 7 installation, most preferably one already installed on your Mac. The installer will check your apps and devices for compatibility, handle the payment, and then provide the license key and download the necessary files. (About.com handily lists all the steps we'll be using).

After the Windows 8 download has finished, you will be asked how you wish to install. Choose Install by creating media (Install now would upgrade your current Windows 7 on your internal drive).

Next choose ISO file and follow the steps. Once the ISO file has been created, burn it to a DVD (if you can't burn ISO files on Windows, download ISO Recorder for free). Also be sure to burn the contents of the ISO to the disk, not just put the ISO file itself on the disk by mistake (like I did ... oops 🙄).

Aside: Why a DVD is Important

If you're in a hurry, feel free to skip ahead to Section C.

If you choose to save the Windows 8 installation media to a USB drive or SD card, it will install, but you'll be left with a broken installation. For me, this meant missing devices (specifically the soundcard no longer showed up in the Windows Device Manager) and Boot Camp causing crashes (accessing the Boot Camp Control Panel, or trying to adjust the brightness using the F1/F2 keys, caused a BAD_POOL_HEADER blue screen of death).

Plenty of other people on these forums have had the same issues, and they seem to believe it's related to the Mac's use of EFI vs. Windows' use of UEFI. Using a USB drive or SD card to install Windows triggers an EFI-based installation, which in turn causes the problems above. It's unclear who's at fault (Apple, Microsoft, Intel, or a combination thereof), but as of December 2012 / OS X 10.8.2 / Boot Camp 5, it's broken.

However, using a DVD to install Windows triggers a legacy BIOS-based installation. For whatever reason, this works just fine: all devices are recognized and Boot Camp installs correctly. The only caveat is not being unable to put the computer into sleep/standby mode with Thunderbolt enclosures (USB 3 on 2012+ Macs should be fine), but this is an issue that other external Thunderbolt devices currently experience too.

It's my guess that Boot Camp 6 will help to fix some or all of these issues, but I'm guessing it's easier to solve the no-standby-mode issue rather than the EFI-vs-UEFI issue, so that's why I'd recommend going the DVD route as others have suggested on these forums. Yes, you lose out on Windows 8's UEFI enhancements, but it's not the end of the world.

Quick tip: You can tell if you're using a BIOS-based installation as you'll briefly see the BIOS flash up when your Mac is booting up. The Windows installer itself will also appear low-res (i.e. around 800x600). If you're using the EFI-based installation, you won't see any BIOS screen and the Windows installer will be high-res (i.e. matching your display's native resolution).

C. Time to Install

Update: If you're using a USB 3 drive, please read Lyrrad's post for how to install Windows 8 without any setup errors.

Once you have your Windows 8 DVD ready (and your license key handy), ensure the DVD is in your optical drive and connect your SSD via Thunderbolt.

Next, boot your Mac whilst holding down the C key to boot from the optical drive (you can also hold down the Option/Alt key and use Startup Manager, if you like).

(To view screenshots of the next steps, check out the About.com Clean Install Guide).

You should now see the Windows 8 logo appear and after a while an activity icon will start spinning. This will take time, since optical drives are slow, so just be patient. (If you're curious, the Windows installer is extracting the files to a RAM disk, so no changes are being made to your Mac's internal drive).

Once the installer appears, choose your language and then press the big Install button (don't choose Repair my PC, as you can't resume the installation later without first restarting your computer).

D. Prepare Your Disk

Next enter your license key, agree to the EULA, and then the installer should next ask what kind of installation you want. It's important to choose a Custom installation, not Upgrade, as this will allow us to choose the install location and to prepare our SSD.

Next you'll be shown a list of drives. If your Mac is like mine, Drive 0 will be your internal drive with its various partitions. If your internal Windows boot manager partition is not NTFS formatted, simple select this partition, then press Drive Options > Format. Except for this, leave the rest of Drive 0 alone! If you need to make changes, use the Mac's Disk Utility instead, as it's more sophisticated than the Windows installer.

Assuming you have no other drives installed, then Drive 1 should be your Thunderbolt / USB 3 SSD drive. Some drives ship as just blank space, in which case you'll need to select Drive 1 and press the Drive Options > New button to create a new (NTFS) partition on your SSD. (Note that Windows will automatically create several smaller recovery partitions later on, just like OS X does, so you don't need to do this yourself).

If your SSD already has partitions, select Drive 1 and then press the Drive Options > Format button. This will wipe any existing data and perform a quick (NTFS) format (this isn't drive intensive, so it's fine for SSDs). Please be careful which partition is selected before formatting it! 😛

When you're ready, and with the Drive 1 partition selected, click Next and then sit back & relax. The Windows installer will now transfer the installation files from the DVD to your SSD. The optical drive is the weakest link here, so don't be alarmed if this process takes a while.

E. Watch Out for the Restart

After all the installation files are copied to your SSD, the Windows installer will restart your Mac. At this point, OS X is still your default startup disk, so when your Mac reboots, hold the Option/Alt key to access the Startup Manager.

If your Mac is like mine, you should see: OS X, OS X Recovery, Windows (yay!) and the Windows DVD. Choose the Windows drive to continue the installation. You will now briefly see a BIOS screen saying Press any key to boot from CD or DVD: ignore this, as booting from the DVD will restart the installation from scratch, whereas we want to continue our existing installation.

If you miss the restart (like I did at first), OS X will boot up like normal, but don't worry! Your Windows installation will still be waiting for you whenever you're ready. Just shutdown your Mac, and then boot up again holding the Option/Alt key as described above.

(As an aside, you can now remove the Windows 8 installation DVD, as we've finished it. However, if you can't remove it yet, never mind, just ignore any further prompts about booting from the DVD).

F. Finish the Windows Installation

You're in the home stretch now. The Windows 8 logo will again appear and you'll see a message about 'Getting devices ready'. (It may also briefly say it's scanning/fixing your drive, but this doesn't seem to be a problem).

After all your devices are ready, your Mac will reboot again, and again you'll need to hold down the Option/Alt key to boot from Windows.

After rebooting, Windows 8 is now installed, and you can begin the setup and personalization guide. At this point, I would advise not to connect to any wired or wireless networks. This is probably being over cautious, but personally I didn't want Windows Update to automatically download any drivers before Boot Camp had been installed. I don't think it actually updates this aggressively, but for safety's sake, I'd advise choosing to connect to a wireless network later.

G. Install the Boot Camp Drivers

After the setup and personalizations complete, Windows 8 is actually ready to use, but you may notice 3-4 devices in the Windows Device Manager that aren't correctly recognised (your internal Mac drive will also be hidden in File Explorer, but don't worry, it's still there! We just need a HFS+ driver to 'see' it).

To fix these issues, go ahead and insert the drive containing the latest Boot Camp drivers, then use File Explorer to start setup.exe. Follow the instructions and then wait whilst Boot Camp installs the relevant drivers.

(You may notice some oddities, like an nVidia logo being shown for ATI-based Macs, and Realtek audio drivers for Cirrus-based systems, but fear not, everything gets installed and configured correctly. The screen may flicker on and off, the screen brightness may change, and the plug-in/unplug sound may chime a few times, but this is all normal).

After Boot Camp has finished, all your devices are now ready, but it's best to reboot one last time. If you plan on using Windows 8 as the default startup disk, go ahead and set that option in OS X using Startup Manager, or otherwise just hold the Option/Alt key whilst booting to select your Windows 8 drive.

H. Tidying Up

Windows 8 is now fully set up and ready to use on your shiny new external SSD; congratulations!

If you already chose to connect to the internet during the setup and personalization process, you can ignore the following steps. However, if you chose not to connect to the internet before, then there are a few last bits of housekeeping that need to be done:

From the Settings charm (or Control Panel), choose the wifi network you wish to connect to and/or plug in your Ethernet cable.
Next select Settings > Change PC settings (at the bottom) > Activate, to activate your copy of Windows (if you don't see this option, your copy of Windows 8 has already been activated). Quick tip: If you see a 'Windows 8 Pro / Build 9200' watermark on your desktop, this means your copy of Windows 8 hasn't been activated yet.
Optional: From Settings > Change PC settings > Users, choose if you want to convert your local account into a Microsoft account. This essentially allows you to sync your settings across other Windows 8/RT devices.
Optional: From Settings > Change PC settings > Windows Update, check for any updates. Do not check for updates before you activate Windows. Doing so causes a bug whereby some updates fail to install (usually failing at the 'configuring ... 98%' stage and then reverting).

That's it! Well done! You rock! 😀

Final Points

Wow, I think that's everything, just a few last points:

Windows treats upgrade media the same as its full versions, so as long as you have a valid license key, you shouldn't need the original Windows 7 disk when installing (even when performing a clean install with upgrade media, like we are here).
Your Thunderbolt / USB 3 drive will show up in Windows 8 as a removable drive (because technically it is, despite having the OS installed on it). For goodness' sake: do not press Eject Thunderbolt or Eject (SSD Drive Name). I'm not brave/stupid enough to find out what happens if you do, but it can't be good.
In a similar fashion, OS X will mount your new Windows 8 drive like any other disk and ask if you want to use it for Time Machine backups. It goes without saying, of course, but choose Don't use 🙂

If I missed anything, or if anything is unclear, just let me know and I'll update this post accordingly. Sorry in advance for the epic length and/or any typos!?

I hope this helps to save some headaches for people wanting to add an SSD drive to their Mac.

Good luck!

Update: LaCie now has Windows drivers for the ASMedia Thunderbolt controller. These add a few more options in Device Manager, including the ability to disable hot-plugging (so you can't accidentally 'unplug' the drive in the Safely Remove Hardware menu, although the Thunderbolt port itself will still be listed as removable as it's controlled by Apple's drivers).

Both the LaCie drives and the Buffalo MiniStation use the same ASMedia 106x controller, so the drivers should work just fine, but of course double-check before installing (Buffalo offers the same drivers, but they're only on their Japanese website at the time of writing).