Installing Windows 8 on an External SSD Guide

Hi guys

I recently installed Windows 8 on an external SSD for my Mac. In the end the process was quite straightforward, but there were quite a few hurdles along the way. I found a lot of useful information here on these forums, so I just wanted to say a big thank you and to post my guide here. Hopefully it will save other people some time. (Sorry for not replying to the other posts directly, but I didn't want to cross-post on so many different threads).

I know not everyone likes Microsoft or Windows, but that aside, for those who want and/or need Windows 8 on an external SSD, here's what worked for me. There are many other ways of doing this (for example, you could change the internal drive instead), but adding an external drive is fairly simple and brings with it a fair amount of flexibility.


What You'll Need

In brief:

• A modern Mac (obviously ^^)
• A Thunderbolt (or USB 3*) hard-drive enclosure
• An SSD drive (if not included with the enclosure)
• A DVD drive
• Windows 8
• Boot Camp drivers
• A blank DVD (a single-layer DVD-R is fine)
• A USB flash drive or SD card

* Update: Sorry for any confusion, but it seems installing Windows 8 on an external USB 3 drive may be more difficult than expected. However, Lyyrad has managed this, so please read his helpful post.
In detail:

• A modern Mac: To get the most out of this, you'll need a Mac made in 2011 or thereafter, as you'll need an IO port fast enough to accommodate an SSD drive. 2011 saw the introduction of Thunderbolt and 2012 brought USB 3 too, both of which are fine for our needs. Firewire 800 and USB 2 may be just about okay for older HDDs, but they'll ruin any speed benefits that an SSD would bring.
• A Thunderbolt (or USB 3) hard-drive enclosure: This is essentially just a case with a small logic board that allows a SATA drive to connect with your Mac. Although Thunderbolt is the fastest and perhaps the most elegant solution, it also carries a large price premium. USB 3 enclosures, whilst not as fast, still offer more than enough bandwidth for our needs and are also cheaper and more readily available. However, the installation process is not as simple. See the Some Buying Advice below for more advice.
• An SSD drive: Although you could use a regular HDD or hybrid drive (like the Seagate Momentus XT), SSDs will bring much improved performance and are now cheap and stable enough for everyday use. Depending on the enclosure you choose, you may or may not have to buy an SSD separately.
• A DVD drive: Depending on your Mac, you may or may not already have one of these. If you don't, thankfully an external USB DVD drive should work fine, just as long as you can boot from it. We'll need this in order to correctly install Windows 8.
• Windows 8: Microsoft are currently offering a cheap Windows 8 Pro upgrade for existing Windows users, so be sure to buy before January 31, 2013. If you already have Windows 7 installed on your Mac, be sure to purchase the Windows 8 upgrade on this machine, as the installer will check your apps and devices for compatibility and also help to download the right version (i.e. if you're using Windows 7 x64, the installer will download Windows 8 x64).
• Boot Camp drivers: You can download these using Boot Camp Assistant on your Mac. Boot Camp 5.x is around 655 MB, so it'll easily fit on a USB drive or SD card (or even a CD-R, if that's how you roll ).
• A blank DVD: I know, I know, but we need to burn the Windows 8 upgrade to DVD in order to ensure maximum compatibility. If you purchased a Windows 8 retail disk instead, then you can ignore this requirement.
• A USB flash drive or SD card: This is just for storing the Boot Camp drivers on.

For your reference, my setup:

• 2011 iMac
• Buffalo Ministation Thunderbolt enclosure
• Plextor M5S 256 GB SSD
• Windows 8 Pro x64 (upgrade)
• Boot Camp 5

Some Buying Advice

If you already have your hard-drive enclosure and drive, you can skip this part. If not, feel free to read on.

Enclosures

USB 3 Pros and Cons

• + Cheap
• + Plenty of choice
• + Compatible with more PCs
• + Should allow Windows to correctly enter standby mode
• - More difficult to install compared to Thunderbolt (please read Lyrrad's post)
• - Not as fast as Thunderbolt (although for our purposes this probably isn't an issue)

Remember to check if the enclosure supports SATA III drives, as some older/cheaper enclosures only support SATA I/II. This isn't the end of the world, as SATA standards are backwards compatible, but if your SSD is rated as SATA III (6 Gbps), then I'd choose a SATA III enclosure too.

Also note that some USB 3 enclosures require a small power brick, whereas others are bus-powered (either requiring one or two USB ports depending on the model you choose). Again, it all works out the same, but bus-powered drives are generally more portable.

Finally, USB 2 drives (and Firewire ones too) will be rejected by the Windows installer as the connection speed is probably deemed too slow. There are workarounds, but really you will need at least USB 3 for a satisfactory experience.

Thunderbolt Pros and Cons

• + The fastest external connection of its type
• + Thunderbolt enclosures are currently premium products (so generally good quality)
• + Intel and Apple designed
• - Thunderbolt enclosures currently carry a large price premium
• - Some enclosures don't ship with a Thunderbolt cable (which is itself expensive)
• - There are currently only a few PCs that have Thunderbolt ports
• - Thunderbolt doesn't currently allow Windows to enter standby mode

Discounting the ridiculously expensive Thunderbolt enclosures and hubs, there are basically three choices at the time of writing (all of which ship with Thunderbolt cables):

• Buffalo MiniStation Thunderbolt: Supports both Thunderbolt and USB 3, bespoke logic board offers great performance, beautiful design, three-year warranty. However, it's not available with an SSD as standard, it's difficult to upgrade, and it's more expensive than the LaCie drive.
• LaCie Rugged: Supports both Thunderbolt and USB 3, available with a 120 GB or 256 GB SSD, not too expensive. However, some reviews say it runs hot under load, it 'only' comes with a two-year warranty, and it's ... very orange (However, the orange removed).
• Seagate GoFlex Thunderbolt Adapter (2.5" and 3.5" versions available): Allows an existing GoFlex or Backup Plus drive to be connected and comes with a three-year warranty. However, the price doesn't include a drive, there's no USB 3 support, and the 2.5" version doesn't offer great performance.

Having read reviews at places like Anandtech, the MiniStation seems like a great product, but please see the warning below.

Buffalo MiniStation Warning

Disassembling this drive is a nightmare It's a beautiful piece of hardware, but Buffalo adheres the drive to the enclosure with a large swathe of strong, double-sided tape. Unless you have experience and the right tools, you will damage this enclosure if you try to change the drive.

The lid is soft plastic, plus the metal scratches easily, and you simply have to apply too much force to remove the drive. I pretty much ruined my enclosure, so please keep this in mind if you're thinking of buying the MiniStation to upgrade the drive: it's not for the faint of heart.

However, once you do access the internals, changing the drive is pretty straightforward. Unscrew and unclip the relevant parts to remove the internal black plastic enclosure, cut the warranty label, then wiggle the drive free from the internal metal enclosure. It ships with a nice Seagate Momentus B HDD (500 GB or 1 TB), so you can either keep this or sell it on eBay etc.

Some SSDs may be slightly too large to fit where the HDD was, in which case you'll need to remove the SSD case and try again. Some SSDs have a warranty label on the case, so think twice before you cut it!

Update: There is already an SSD-based MiniStation in Japan, so these should be available internationally in 2013. This way you won't have to mod the drive yourself and thus your warranty/enclosure/sanity will all remain intact.

SSDs

I'll keep this brief, as there's already mountains of information out there, but essentially SSDs bring large performance benefits over traditional HDDs. Yes, they're more expensive, but prices are have no dropped to at or around US$1/GB, which is much better than it used to be.

Aside from the different brands and their varying firmware updates and warranties, most SSDs boil down to: capacity, controller and memory. 60 GB 2.5" drives are about the smallest capacity available now, but note that 60 GB variants often run slower than their larger capacity cousins (in order to keep costs down). Look for 120-256 GB drives for the best price/performance ratio.

The controller basically handles how the drive works. There are many variants on the market, but the two most common brands are SandForce and Marvell. Both have their strengths and weaknesses, so read some reviews to get a feel for how they're optimised (and read Anandtech to learn more about SandForce's TRIM performance issues with incompressible data).

Finally, there are basically three types of memory: SLC, MLC and TLC. In that order, they go from the longest endurance and most expensive, to the weakest endurance and least expensive. MLC tends to hit the sweet spot for most consumer applications, so it is now the most common choice.

In terms of brands, Intel SSDs have a good reputation for their reliability, but they do carry somewhat of a price premium. Samsung SSDs offer great performance, but again aren't cheap. However, there are many other decent brands to consider (Plextor, OCZ, Corsair etc.).


A Few Warnings

This should be obvious, but it's worth repeating before we begin:

• Always back up your data before messing with your OS: Even straightforward upgrades can go awry, and you'll be sorry if you lose any important data, so don't take any risks.
• You may void your enclosure and/or drive warranty by doing this: Replacing an enclosure's original drive will void the warranty, and if you have remove an SSD drive from its case, that'll probably void its warranty too. Since most of these products offer generous three-year deals, think carefully before proceeding.
• You will have to live with some compromises: If you follow these instructions, you'll lose the ability to put Windows into sleep mode when using a Thunderbolt enclosure (USB 3 should be fine, though, as this issue seems to be unique to Thunderbolt on Windows). It's a small bug that'll hopefully be fixed in the future, but think ahead if you can accept this.
• Don't blame me if all goes wrong: What works for one person might not work for you. As far as I know, these instructions should work nicely across many different configurations, but your experiences may vary.

If your Mac is your primary computer, you should choose a time to upgrade when you need it the least (i.e. a quite evening or weekend). Start to finish, you should only need an hour or so, but always plan for the worst.

Continued below ...

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:

1. 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 ...
2. 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).

Good luck, nikmoz! Hope it all goes smoothly for you.

P.S. Since your Mac and external drive both have USB 3 support, I'd suggest using that in order to keep Windows 8's sleep mode functionality.

Hi all

Sorry, I forgot to check back recently

rezwits said:

Been thinking about a both of those drives, (LaCie & Buffalo)

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I think they're both good options, so it just depends on your budget and other needs. Neither one should disappoint you

P.S. Buffalo Japan are already selling SSD versions of the Thunderbolt MiniStation, so I guess we'll see the same models released internationally next year (if you're not in a rush and don't want to mod your drive/break the warranty). If you want to buy now and don't want to swap the drive yourself, then LaCie is your best/only choice.

Gascogne said:

I got some problems installing windows 8 on my external LaCie Thunderbolt SSD 512Gb.

Click to expand...

It sounds like you've done everything right I don't know about installing from a USB stick, as that'll trigger an EFI-based install which can cause problems later on, but this usually only occurs after the install.

Some people suggest an 0x80004005 error can be caused by a corrupt disk image, but I'm not sure how reliable that information is. I guess you've tried re-downloading the Windows 8 installer again? I'll let you know if I find anything else that might help.

tmanto02 said:

I just tried and failed. I got to the section where you select the ssd from the list of drives, however it said that windows cannot be installed onto USB?

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I think Windows refuses to install on external USB 2 drives because the connection is deemed unsuitable (probably because USB 2 and Firewire are quite slow). You should be okay once your USB 3 enclosure arrives, assuming you have a USB 3 capable Mac, but I've not been able to test this myself.

iManni said:

i´m not sure if i should order the lacie(329 euro apple.at) if it does not work,can anyone say about the speed of Windows 8 on a SSD?

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That price sounds about right for the LaCie 256 GB SSD, but be sure to shop around for a good Christmas deal. As for speeds, I haven't benchmarked my Buffalo/Plextor system, but it scores a maximum of 7.9/7.9 in the Windows Performance Index, so I guess the LaCie drive should be similar.

simon567 said:

A couple of points that may be useful to people...

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Thanks for the info! That's good to know about XP, and you're right about the LaCie drive, I forgot that the rubber part is removable Congrats on getting everything working!

tmanto02 said:

Have you actually tried USB? Because mine did not work

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No, sorry, I haven't been able to test this myself. My iMac is a 2011 model, so it only supports USB 2. I have[/u] tried USB 2, and I know the Windows installer refuses to proceed on external USB 2 drives (maybe it can be hacked, but I'm not sure). USB 3 should work, because it's fast enough and Windows 8 includes native USB 3 drivers, but I can't test this myself.

...

P.S. A small, but important update to the original guide: it seems you do need a partition on your internal drive in order for Windows 8 to install correctly.

If you just try:

• Internal drive: OS X (HFS+)
• External drive: Windows 8 (NTFS)

Then the Windows 8 installer will complain about not being able to partition the (external) drive or something like that. You're then left with no choice but to quit the install process.

To fix this, just create a partition on the internal drive before you begin the Windows 8 install. It can be small (20 MB should be enough), but you can make it much larger if you want to use it like any other normal partition.

OS X's Disk Utility doesn't support formatting new partitions as NTFS, but you can use FAT32 first then use the Windows installer to format it again as NTFS. You'll then have:

• Internal drive: OS X (HFS+), Windows 8 'boot' (NTFS)
• External drive: Windows 8 'proper' (NTFS)

You still select the external drive when installing, but now Windows will use the internal partition to store its boot manager files, and all the other files will be installed on external drive. This way OS X's Startup Disk is also happy, because it can recognize a Windows installation on the internal hard drive, even though the actual Windows 8 files are all on the external drive.

You can stop reading now, but in case you're curious, Windows 8's Disk Management app should show your drives as follows:

• Internal drive: OS X 'proper' (HFS+), OS X 'recovery' (HFS+), Windows 8 'boot' (NTFS, marked 'System, Active')
• External drive: Windows 8 'proper' (NTFS, marked 'Boot' and many other things)

In Windows parlance, a 'system' partition is where the boot manager is located ('active' just means that partition can be used to boot into Windows). Confusingly, the 'boot' partition is where the actual copy of Windows resides. Normally the 'system' and 'boot' partitions are one and the same, but here the Windows 8 installer separates them and then automatically links everything together so Windows starts up normally.

Like I say, you don't need to know this, but just don't worry if your 'system' and 'boot' partition aren't the same.

Merry Christmas!

hfg said:

Thanks and Merry Christmas to forum members...

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Merry Christmas, Howard!

Lyrrad said:

As an update, I got Windows 8 installed to an external USB 3 Drive using a MacBook Pro Retina 15".

I followed the instructions in this post to create a Windows 8 To Go drive. I can then boot by pressing ALT upon startup.

I did notice in that thread that some people were experiencing issues with certain USB 3 enclosures. I'm using the BlacX 5G after installing the UASP firmware update.

I do notice that after a reboot, the drive isn't detected, but unplugging and plugging it back in gets it to appear.

I installed the Boot Camp drivers and they seem to work fine.

I'm using a regular disk drive, but I'll probably get an SSD for this setup later.

Click to expand...

Thanks so much for this, Lyrrad. I'm very sorry for the inconvenience, as I honestly thought USB 3 should act much like Thunderbolt does, despite the technical differences. However, it seems I was wrong, so I've updated the original guide and linked to your post instead (hope you don't mind). Thanks again for sharing this; it's really useful for everyone else out there. Happy Xmas!

Gascogne said:

The install process is possible now but windows complains about no boot function when selecting which harddrive to install on. (But clicking next works)

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Sorry you're still having problems, Gascogne

I previously encountered a similar problem when messing around with my partitions, and the following helped me to fix the 'winload' error. It's all detailed on Microsoft's website, but basically we're going to try to fix the broken Windows boot manager:

Update: I just saw your edit. I guess you did the following and none of it worked?

1. Start your Mac and boot into the Windows 8 installer (in this case, either a USB or DVD-based installer is fine)
2. Once the installer starts, choose your language options, press 'Next', then press 'Repair your computer' (don't press 'Install' )
3. (This next part is from memory, so you might need to look around a little) In the repair menu, press 'Advanced Options', then press 'Command Prompt'
4. In the command prompt, type bootrec /scanos It should find one Windows installation [If it doesn't find anything, stop now (type exit or close the window), then shut down your computer]
5. Assuming a Windows installation was found, now type bootrec /rebuildbcd Another scan will be performed, the Windows installation will be found, then you'll be asked if you want to add it. Type y for 'yes' to include this Windows installation in the boot manager.
6. Assuming everything above went smoothly, now type bootrec /fixmbr followed by bootrec /fixboot (both of which should complete successfully). These two commands probably aren't needed, but it doesn't hurt to try
7. Now type exit or close the command prompt window, choose the option to shut down your computer, then boot your Mac again. Hopefully now the 'winload' error will be fixed and Windows will boot correctly.

If this doesn't work then there are some other options, but they basically involve starting from scratch. Anyway, try the above and see if it works.

Gascogne said:

The commands list worked but windows still is refusing due to missing winload.exe file.

So next step is to start from scratch then? I feel this is going to be long night for me..

Click to expand...

That's odd There's maybe two more things to check before you start from scratch:

1. Check the boot manager is correct

Back in the command prompt above, type bcdedit /v You'll then see your boot manager information. Check the first part ('Windows Boot Manager'):

1. 'device' is on an internal drive partition
2. 'default' (a long ID) is the same ID as your Windows Thunderbolt drive partition below

Now check the second part ('Windows Load Manager'):

1. 'device' is on your Windows Thunderbolt drive partition
2. 'path' is something like '\Windows\system32\winload.exe'
3. 'osdevice' is the same partition letter as 'device'
4. 'systemroot' is '\Windows'

If all this is correct, next let's check the partitions are correct.

2. Check the partitions are correct

Still in the command prompt:

1. Type diskpart and wait for the app to load
2. Now type list disk to see all your drives (Disk 0 is probably your internal drive, then Disk 1 and Disk 2 are probably your external Thunderbolt drives)
3. Type select disk 0 (assuming Disk 0 is your internal drive)
4. Now type list partition to see all partitions on this drive
5. Find the boot manager partition mentioned above (either 'storage' or 'windows boot', based on your descriptions), then type select partition x where 'x' is the partition number
6. Type detail partition and you should see this boot manager partition is 'Active' and the info section should say 'System'. If it says 'Inactive', and you're sure this is where the boot manager files are located, next type active. If it was already active, skip to the next step.
7. Now type select partition y where 'y' is your other NTFS partition (e.g. if you just checked 'windows boot', now check 'storage')
8. Type detail partition again and ensure that this other partition is inactive and not labelled 'System'. If this is correct, type exit twice to quit. However, if it is marked as 'active', now type inactive, then proceed to exit.

All we just did is make sure the boot manager and partitions are correctly set up so that the boot sequence will work correctly. If everything looked fine, and you still receive a 'winload' error, then sadly your last resort is to reinstall

If your have no important files, remember to format your Windows Thunderbolt drive and the internal Windows boot partition during the installation process (just as a precaution). Also if you can, try to do a DVD-based install this time, as even though it's slower, it does seem to be more stable.

Good luck!