Q: How to run Boot Camp on External Hard Drive?

Anyone here tried on of the solutions given here with a OWC Mercury Elite Pro Dual TB (2-bay) enclosure? I managed to get both OSX 10.10.1 and W7 working on a DeLock 2.5" TB enclosure, but as I have only one of these, I need to swap drives. That's too much of a hassle.

Just bought the Pro Dual, but that darned box just refuses to boot W7 at all. With a standard OSX/Bootcamp W7 internal disk, if the Pro Dual is connected via TB, only OSX boots... Windows shows a black screen with blinking cursor.

Thymen

Can you post the output of diskutil list with the external TB enclosure connected?

Loner T, Sorry for the late reply, have been quite busy.

The listing:

/dev/disk0  >> internal HDD

  #:                      TYPE NAME                    SIZE      IDENTIFIER

  0:      GUID_partition_scheme                        *1.0 TB    disk0

  1:                        EFI EFI                    209.7 MB  disk0s1

  2:                  Apple_HFS Macintosh HD            798.3 GB  disk0s2

  3:                Apple_Boot Recovery HD            650.0 MB  disk0s3

  4:      Microsoft Basic Data BOOTCAMP                201.0 GB  disk0s4

/dev/disk1  >> W7 SSD in DeLock TB housing

  #:                      TYPE NAME                    SIZE      IDENTIFIER

  0:      GUID_partition_scheme                        *250.1 GB  disk1

  1:                        EFI EFI                    209.7 MB  disk1s1

  2:      Microsoft Basic Data W7SSD                  224.8 GB  disk1s2

/dev/disk2  >> OSX SSD in OWC Elite Dual Pro TB housing, in the bootable bay

  #:                      TYPE NAME                    SIZE      IDENTIFIER

  0:      GUID_partition_scheme                        *500.1 GB  disk2

  1:                        EFI EFI                    209.7 MB  disk2s1

  2:                  Apple_HFS SSD                    499.2 GB  disk2s2

  3:                Apple_Boot Recovery HD            650.0 MB  disk2s3

Now, if I keep the Elite Pro switched on a boot time, neither W7 in disk 0, or disk 1, starts. I get a black screen with blinking cursor.

Switch off disk 2 (the Elite Pro), and OSX @ disk 0, W7 @ disk 0 and W7 @ disk 1 boot without a hitch.

I solved the problem, by putting the plug of the Elite Pro in a switched plug/socket housing. Switch ON for booting OSX @ disk 2, switch OFF for booting Windows @ disk 0 or 1, or OSX @ disk 0.

It is a solution, albeit not the one I had in mind.... If anyone knows how to circumvent the problem, let me know.

Oh yes, people @ OWC: you state the Elite @ TB is not compatible with BootCamp: it is the other way around: BootCamp is not compatible with the Elite @ TB. Quite a difference...

Thymen

With everything on, as a test, execute a SMC Reset and a PRAM(NVRAM) reset. There is information in the NVRAM which can cause Bootcamp to run into issues.

The black screen with a blinking underline cursor indicates that the Windows bootmanager has failed to load the bootblock. There is a tool called EasyBCD which may also prove helpful, it allows you to add more than one Windows in the boot options.

Can you post the output of the following commands?

sudo fdisk /dev/disk0

sudo fdisk /dev/disk1

I already did the SMC/PRAM reset; I used EasyBCD to change the names of the windows, and shorten the boot pause.

When I start the system with Option key pressed, I see one Windows boot option only; select that one, then the Windows boot manager kicks in and allows me to choose between either one of the windows I have installed: the Bootcamp one on the internal hdd, the other one on the TB SSD. Select StarUp disk from within OSX shows both windows installatiiions, though.

The SSD windows I have installed manually, from within the W7 Bootcamp. I used a script that custom installs windows, in order to use the GPT partition style. If you install windows by selecting the installation DVD, the target disk needs to be MBR style. Works, and with a 256 GB disk it is no problem, but I prefer the GPT style. 

Howto: see http://www.intowindows.com/how-to-install-windows-7-to-usb-external-hard-drive-m ust-read/

Create a flash drive using the Bootcamp assistant to hold all the drivers, and run bootcamp.exe on it after you have installed windows. Did not try this with USB disk, but it might work...

Not sure, but for Windows 8.1, it may be possible to directly install from the dvd, without going through Bootcamp and having windows installed on the HDD. W8.1 uses EFI, so perhaps it installs the boot info on the external disk, where W7 relies on the EFI on the internal disk to get started. But I have spent enough money so far, and W7 works fine for me.

The listing:

Disk: /dev/disk0 geometry: 121601/255/63 [1953525168 sectors]  >>> HDD !!!

Signature: 0xAA55

         Starting       Ending

#: id  cyl  hd sec -  cyl  hd sec [     start -       size]

------------------------------------------------------------------------

1: EE 1023 254  63 - 1023 254  63 [         1 -     409639] <Unknown ID>

2: AF 1023 254  63 - 1023 254  63 [    409640 - 1559267840] HFS+       

3: AB 1023 254  63 - 1023 254  63 [1559677480 -    1269536] Darwin Boot

*4: 07 1023 254  63 - 1023 254  63 [1560948736 -  392574976] HPFS/QNX/AUX

Disk: /dev/disk1 geometry: 30401/255/63 [488397168 sectors] >>>> SSD !!!

Signature: 0xAA55

         Starting       Ending

#: id  cyl  hd sec -  cyl  hd sec [     start -       size]

------------------------------------------------------------------------

1: EE 1023 254  63 - 1023 254  63 [         1 -  488397167] <Unknown ID>

2: 00    0   0   0 -    0   0   0 [         0 -          0] unused     

3: 00    0   0   0 -    0   0   0 [         0 -          0] unused     

4: 00    0   0   0 -    0   0   0 [         0 -          0] unused     

The SSD installation of W7 does not seem to be EFI. It has a GPT and a Protective MBR, but since it has no MBR, Apple's Bootmanager cannot boot it. It can boot W7 on disk0 only. Bootcamp has no knowledge of any dual-boot within Windows.

When I start the system with Option key pressed, I see one Windows boot option only; select that one, then the Windows boot manager kicks in and allows me to choose between either one of the windows I have installed: the Bootcamp one on the internal hdd, the other one on the TB SSD.

This behavior is what you see as you have documented.

Select StarUp disk from within OSX shows both windows installatiiions, though.

Because there are two GPT entries and NTFS file systems (disk0s4 and disk1s2). It switches to CSM-BIOS and points to the respective Bootloader. There is nothing for it to use on the SSD, hence the blinking cursor.

Since both the OWC and the DeLock are TB devices, how are they connected? What type of Mac are you using?

Loner T;

I have a 27" iMac, mid 2011 model. Has two Thunderbolt ports. The OWC enclosure with the OSX SSD is connected directly to one port, the DeLock enclosure with the W7 SSD is daisy chained after a CallDigit TB dock. But, while testing, both were directly connected to a TB port on the iMac.

I tried multiple scenarios:

1. internal HDD with OSX only, install W7 directly from dvd on MBR/NTFS SSD; installs, but does not show at Option-boot; shows as StartUp Disk in OSX, but does not boot.
2. Internal HDD with OSX only, attempt to install directly from dvd on GPT/NTFS disk; Windows refuses to install on GPT style disk
3. Internal HDD with OSX and W7 via Bootcamp, install W7 directly from dvd on MBR/NTFS SSD; installs, shows 1 x Windows at Option-boot and allows to select either one of the W7 installations at the Windows bootmanager; external W7 shows at StartUp Disk, but boots as if via Option-boot.
4. Internal HDD with OSX and W7 via Bootcamp, install W7 directly from dvd on GPT/NTFS SSD; Windows refuses to install on GPT disk
5. Internal HDD with OSX and W7 via Bootcamp, while in W7 @ internal HDD, install W7 via script according the link in my previous post. Disk = GPT, formatted NTFS.  Installs, shows 1 x Windows at Option-boot and allows to select either one of the W7 installations at the Windows bootmanager; external W7 shows as StartUp Disk in OSX, but boots as if via Option-boot.

I have set up my system now according item 5, plus a switch to turn the OWC on/off. I still wonder though why the OWC enclosure hijacks the boot process, and causes all these troubles. The DeLock enclosure does not do that. Perhaps because the OWC has daisy chaining capabilities?

If one installs OSX on an external disk, it creates an EFI system partition on that disk. I assume that all that is required to boot from that disk is in that partition. I cannot remove my internal disk, so can't test it. It seems to me that W7 relies on the boot info stored by Bootcamp on the EFI of the internal disk.  Now I wonder if W8.1, since (afaik) it uses EFI bootmanagement, stores the boot info on the EFI system partition on the external disk as OSX does, and therefor can be installed/booted without having Windows installed on the internal drive. And perhaps the same for Linux?

Possible perhaps, but I do not have W8.1 available. Could have downloaded a trial ISO, but I have done enough installation trial and error for the time being...

Can I suggest this configuration?

Remove W7 SSD from DeLock and put it in the OWC EDP bootable bay (current disk1 in OWC EDP).

Disconnect the DeLock (which should now have the OSX - current disk2).

Test individually for W7 SSD and OSX and then directly connect to iMac and test again.

W8+ seems to be much better at EFI support than W7 does. W7 EFI has given me problems on Graphics and Audio.

You also have a TB (v1) iMac. You can take the two external enclosures to in the configuration of your choice to the nearest Apple Store and try your test scenarios on a 2013/2014 iMac is a 'full' UEFI Mac and has TB (v2).

Loner T;

I tried the config you propose: the W7 SSD in the OWC enclosure, does NOT boot, no matter how you install it. Also: with W7 perfectly running on the Internal disk via BootCamp, and NO disk, or and UNFORMATTED disk, or a FORMATTED disk, or a properly working OSX SSD in the OWC's bootable bay.... connect via TB and booting the internal W7 yields the black screen/blinking cursor.

When the OWC arrived, I had the OSX SSD in the DeLock enclosure, but I already had the W7 SSD prepared and tested in the DeLock as well. Ran perfectly either way. First thing I did was to put the W7 SSD in the OWC: no go! black screen/blinking cursor. I subsequently tried all possible combinations. Must have re-installed W7 perhaps 6 times or so, in various way. Result were alway the same.

As I mentioned before, the Elite Pro Dual @ TB is not not-Bootcamp compatible, but the other way around: Bootcamp is not Elite Pro @ TB compatible. At least, in MY set-up.

As soon as I have some new energy, and curiosity is getting the better of me, I'll try to get a trial W8.1 disk or flash drive, and see if I can get that combo working. But NOT during Christmas, that's for sure!

I do not have an OWC EDP to test with, but I will try to get one. It may take me a couple of weeks though. I am curious, too.

If DeLock TB works with BC, but OWC EDP does not, I suspect that OWC is not being candid about how they have implemented it.

One could try to get into a discussion with OWC about how 'BootCamp not supported' has to be interpreted, but even if you win the argument, it would be a Phyrric victory. Had I known before, I would have gotten another DeLock box. Half the price, on SSD also 10% faster then the OWC, and supports both OSX and Windows without having to disconnect one drive.

My personal opinion: with OWC product it is best to read all the specs, follow all links and read the manuals, before you buy. Or you may be in for an unpleasant surprise.

Would I by OWC gear again? Probably not...

Do you have an option to return the OWC EDP?

I thought about returning it. But, I have to admit... it is a nice, solid box. I like its build. I once ordered an 2-bay USB RAID box for my NAS, from the cheaper segment of the market, but that one was too flimsy, too noisy and already DOA. That one I returned.

It is not the product itself that ticked me off, but that I had to spend two days trying to figure out how to make it work, due to the lack of information. It should have been stated more clearly what the limitations are. But, I'll use the OWC as I have it now, with the switch. Adds 30 seconds to the process of booting into the other OS, which is acceptable.

Thank you for the guided steps. My Retina iMac can now boot Win 8.1 from an external SSD via USB 3. The only change was #8 needed to be CREATE PARTITION PRIMARY.

Cool guide. I'll try it out