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bmac89

macrumors 65816
Original poster
Aug 3, 2014
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hello,

I am wondering whether it is possible to install and boot windows 10 preview from an external hard drive?
The external hard drive is running Yosemite.

You can boot OSX from an external so I though maybe bootcamp might work too. However from my attempts it seems an internal drive may be necessary?

When I boot into Yosemite external and use bootcamp assistant it says there is not enough free space on the startup disk. Yosemite external has plenty free space but the internal drive does not so I can not progress.

Thanks
 
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Blackstick

macrumors 65816
Aug 11, 2014
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Windows won't boot from an external hard drive, however, you can install Windows 10 as a virtual machine and the VM file can reside on an external.
 
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TPadden

macrumors 6502a
Oct 28, 2010
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Windows won't boot from an external hard drive, however, you can install Windows 10 as a virtual machine and the VM file can reside on an external.

I've never had a problem booting from external drives, USB and Firewire, using either Windows 8.1 or 10 Technical Preview.

I also have not had any problem installing from ISO file to any USB drive (external SSD) using transportable wintousb with it's wintogo limitations (can't see internal drives, etc.). I currently have both Win 10 and Win 8.1 running from bootable SSD's in cheap USB3 enclosures (with UASP protocol they are FAST) with no problems booting with either the Option key boot or selecting as Startup drive from System Preference on my MBA and Mini.
 
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bmac89

macrumors 65816
Original poster
Aug 3, 2014
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I've never had a problem booting from external drives, USB and Firewire, using either Windows 8.1 or 10 Technical Preview. Even USB drives work fine using a windows clone (free EaseUS Partition Master) of the bootcamp drive.

I also have not had any problem installing from ISO file to any USB drive (external SSD) using transportable wintousb with it's wintogo limitations (can't see internal drives, etc.). I currently have both Win 10 and Win 8.1 running from bootable SSD's in cheap USB3 enclosures (with UASP protocol they are FAST) with no problems booting with either the Option key boot or selecting as Startup drive from System Preference on my MBA and Mini.

Thanks for the helpful replies. I have had a look at WintoGo and read all instructions.

However I am wondering... if I was to clone a bootcamp drive or install windows using WintoGo is there any preparation I need to do with the external hard drive?

For example is it possible to clone and boot windows onto an external hard drive which is formatted and partitioned as Mac OS Journaled Guide Partition Table? Or should it be formatted as something else? I am hoping to install windows onto a separate partition of the external drive which also contains a bootable Mac OSX partition.

Many thanks.
 
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TPadden

macrumors 6502a
Oct 28, 2010
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Thanks for the helpful replies. I have had a look at WintoGo and read all instructions.

However I am wondering... if I was to clone a bootcamp drive or install windows using WintoGo is there any preparation I need to do with the external hard drive?

For example is it possible to clone and boot windows onto an external hard drive which is formatted and partitioned as Mac OS Journaled Guide Partition Table? Or should it be formatted as something else? I am hoping to install windows onto a separate partition on external drive which also contains bootable Mac OSX.

Many thanks.

The windows partition will have to be NTFS. It can be done but there are several ways to do what you want and it will be time consuming, error prone, and the steps will be different depending on what hardware you have, the programs you use to do partitioning, cloning, and OS ISO's.

Look at Wintousb vice Wintogo! Wintousb is really easy to use, particularly with Windows 10 since there is a universal OS activation key good until about next spring. Otherwise the Windows OS will need reactivation any time you use it on a different computer.

One way to do it on an external drive would be to simply use Carbon Copy Clone to clone your OSX to a larger drive. Then option boot to that drive and partition it using OSX Drive Utilities with an exfat partition. Next plug the drive into a Windows machine, the exfat partition will show up, format it NTFS, download the Win10 Technical Preview ISO (noting the activation code), run Wintousb select the ISO, and simply select the same NFTS partition as system and boot.

Problems not knowing the hardware available to you, will include whether the drive will be MBR or GPT (GUID) partitioned and whether your motherboard supports UEFI.

For me, with a desktop running Windows 8.1, a Mac Mini running Yosemite, a SSD with USB3 enclosure, Carbon Copy on the MAC, Win 10 ISO on the Win desktop as well as free Wintousb, Apple's bootcamp driver folder, and free EaseUS partitioning program, it was easy and quick. :cool:

I have a Bootable SSD USB3 250GB with Windows 10 to play with on my MBA, Mac Mini, and Windows Desktop.

Doing it all on a MAC would also be doable but would require a working Windows Bootcamp and a lot of "option" key booting :).
 
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Fzang

macrumors 65816
Jun 15, 2013
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The windows partition will have to be NTFS. It can be done but there are several ways to do what you want and it will be time consuming, error prone, and the steps will be different depending on what hardware you have, the programs you use to do partitioning, cloning, and OS ISO's.

Look at Wintousb vice Wintogo! Wintousb is really easy to use, particularly with Windows 10 since there is a universal OS activation key good until about next spring. Otherwise the Windows OS will need reactivation any time you use it on a different computer.

One way to do it on an external drive would be to simply use Carbon Copy Clone to clone your OSX to a larger drive. Then option boot to that drive and partition it using OSX Drive Utilities with an exfat partition. Next plug the drive into a Windows machine, the exfat partition will show up, format it NTFS, download the Win10 Technical Preview ISO (noting the activation code), run Wintousb select the ISO, and simply select the same NFTS partition as system and boot.

Problems not knowing the hardware available to you, will include whether the drive will be MBR or GPT (GUID) partitioned and whether your motherboard supports UEFI.

For me, with a desktop running Windows 8.1, a Mac Mini running Yosemite, a SSD with USB3 enclosure, Carbon Copy on the MAC, Win 10 ISO on the Win desktop as well as free Wintousb, Apple's bootcamp driver folder, and free EaseUS partitioning program, it was easy and quick. :cool:

I have a Bootable SSD USB3 250GB with Windows 10 to play with on my MBA, Mac Mini, and Windows Desktop.

Doing it all on a MAC would also be doable but would require a working Windows Bootcamp and a lot of "option" key booting :).

Amazing. I didn't even know about that! I really want Windows to install some games, but I have huge trouble installing it alongside Yosemite. I'll whip out my external USB 3 drive and see if I can make it work.
 
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TPadden

macrumors 6502a
Oct 28, 2010
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Amazing. I didn't even know about that! I really want Windows to install some games, but I have huge trouble installing it alongside Yosemite. I'll whip out my external USB 3 drive and see if I can make it work.

A word of caution: there is a world of difference in speed between a USB 3 thumb drive and a SSD in a USB 3 enclosure.
 

Fzang

macrumors 65816
Jun 15, 2013
1,315
1,081
A word of caution: there is a world of difference in speed between a USB 3 thumb drive and a SSD in a USB 3 enclosure.

Mine's a laptop-sized HDD in a USB 3 enclosure. I bet it runs at 4200 RPM.

On second thoughts, I might not try this.
 

bmac89

macrumors 65816
Original poster
Aug 3, 2014
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On a side note....

Will Windows 10 Preview bootcamp successfully on my Imac running Snow Leopard 10.6.8 or does this require a newer OSX? I am referring to internal drive.

Thanks
 

tpaxadpom

macrumors newbie
Oct 17, 2014
2
0
The windows partition will have to be NTFS. It can be done but there are several ways to do what you want and it will be time consuming, error prone, and the steps will be different depending on what hardware you have, the programs you use to do partitioning, cloning, and OS ISO's.

Look at Wintousb vice Wintogo! Wintousb is really easy to use, particularly with Windows 10 since there is a universal OS activation key good until about next spring. Otherwise the Windows OS will need reactivation any time you use it on a different computer.

One way to do it on an external drive would be to simply use Carbon Copy Clone to clone your OSX to a larger drive. Then option boot to that drive and partition it using OSX Drive Utilities with an exfat partition. Next plug the drive into a Windows machine, the exfat partition will show up, format it NTFS, download the Win10 Technical Preview ISO (noting the activation code), run Wintousb select the ISO, and simply select the same NFTS partition as system and boot.

Problems not knowing the hardware available to you, will include whether the drive will be MBR or GPT (GUID) partitioned and whether your motherboard supports UEFI.

For me, with a desktop running Windows 8.1, a Mac Mini running Yosemite, a SSD with USB3 enclosure, Carbon Copy on the MAC, Win 10 ISO on the Win desktop as well as free Wintousb, Apple's bootcamp driver folder, and free EaseUS partitioning program, it was easy and quick. :cool:

I have a Bootable SSD USB3 250GB with Windows 10 to play with on my MBA, Mac Mini, and Windows Desktop.

Doing it all on a MAC would also be doable but would require a working Windows Bootcamp and a lot of "option" key booting :).
I've created windows to go 8 and windows to go 2012 server using manual commands (imagex). I am not able to boot on my mac pro (early 2011) with bootcamp windows 7 installed. I know windows to go drives are fine as I am able to boot on other PC's and Mac's. Is there a trick to get it working on my mac? Using Option during boot doesn't detect windows to go drives. I have tried refit and refind, though when I select windows usb drive the screen goes black with "-" flashing. WinPE (fat32) is detected using Options and boots just fine on my mac.
 

steve62388

macrumors 68040
Apr 23, 2013
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I've never had a problem booting from external drives, USB and Firewire, using either Windows 8.1 or 10 Technical Preview. Even USB drives work fine using a windows clone (free EaseUS Partition Master) of the bootcamp drive.

Really, how do you do that? Because their FAQ states, "EaseUS Partition Master cannot move a partition to another physical hard drive."

So how would you move the partition on your internal Bootcamp drive to an external USB disk?
 

TPadden

macrumors 6502a
Oct 28, 2010
771
452
Really, how do you do that? Because their FAQ states, "EaseUS Partition Master cannot move a partition to another physical hard drive."

So how would you move the partition on your internal Bootcamp drive to an external USB disk?

I told you how I set up Windows to run on a Mac external USB SSD drive using WintoUSB ... the only thing I use EaseUS for was re-sizing and getting rid of partitions after I had Windows 10 running (WintoUSB) on the USB SSD; I have used it also to Disk copy after I had Windows running.

I've never used Bootcamp within OSX to set up the drives; so I've NEVER had a Bootcamp partition running on an internal drive. I only use the Bootcamp drivers on the external after I have a working Windows drive / partition.
 

steve62388

macrumors 68040
Apr 23, 2013
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I told you how I set up Windows to run on a Mac external USB SSD drive using WintoUSB ... the only thing I use EaseUS for was re-sizing and getting rid of partitions after I had Windows 10 running (WintoUSB) on the USB SSD; I have used it also to Disk copy after I had Windows running.

I've never used Bootcamp within OSX to set up the drives; so I've NEVER had a Bootcamp partition running on an internal drive. I only use the Bootcamp drivers on the external after I have a working Windows drive / partition.

Right, well I tried WintoUSB and it doesn't work. It doesn't support drives with 4k sectors, which manufacturers transitioned to in 2011 [source: http://www.tomshardware.com/reviews/advanced-format-4k-sector-size-hard-drive,2759.html].

So I guess they are quite behind the times.
 

TPadden

macrumors 6502a
Oct 28, 2010
771
452
Right, well I tried WintoUSB and it doesn't work. It doesn't support drives with 4k sectors, which manufacturers transitioned to in 2011 [source: http://www.tomshardware.com/reviews/advanced-format-4k-sector-size-hard-drive,2759.html].

So I guess they are quite behind the times.
Don't know what your problem is?????

I'm running both Win 8.1 and Win 10 on 2 separate external SSD USB 3.0 drives that I used WintoUSB to build, both are formatted NTFS 4k sectors.

Your reference tells me NOTHING. How about a reference where WintoUSB won't work with 4k sectors?
 

steve62388

macrumors 68040
Apr 23, 2013
3,100
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Don't know what your problem is?????

I'm running both Win 8.1 and Win 10 on 2 separate external SSD USB 3.0 drives that I used WintoUSB to build, both are formatted NTFS 4k sectors.

Your reference tells me NOTHING. How about a reference where WintoUSB won't work with 4k sectors?

How about the program itself and support staff on their forums?

http://www.easyuefi.com/forums/showthread.php?tid=24&pid=60#pid60

dyyrn.png
 
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TPadden

macrumors 6502a
Oct 28, 2010
771
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How about the program itself and support staff on their forums?

http://www.easyuefi.com/forums/showthread.php?tid=24&pid=60#pid60

Image
I think I now understand your problem. That's because WintoUSB doesn't support the formatting process. Don't use WintoUSB to format. Try formatting the drive first, before running WintoUSB, run WintoUSB, select an ISO, select the drive, and you should go straight to the select system and boot partition menu/ page......

I'm going to redo another drive to make sure that's how I did it.........
 
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TPadden

macrumors 6502a
Oct 28, 2010
771
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I think I now understand your problem.....
I'm going to redo another drive to make sure that's how I did it.........

OK, just took an external USB3 250GB SSD, formatted it NTFS 4K Sectors, ran WintoUSB ...... selected Win 10 ISO build 9879, selected the SSD drive, it went right to the select boot and sysetms partitions (I selected the same partition), it went right to installing...... 4 minutes later I copied Bootcamp 5.1.5621 to the drive. I then plugged it into my Mac Mini and booted right into Win 10, I then ran the Bootcamp setup for drivers and was done.. :cool:


....... just plugged the same drive into my MBA, "option" booted right into Windows 10 Build 9879, ran setup for Bootcamp 5.1.5640, everything is great, couldn't be simpler, Windows 10 runs on my Mini and MBA from a fast external SSB drive. :).
 
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steve62388

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Apr 23, 2013
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OK, just took an external USB3 250GB SSD, formatted it NTFS 4K Sectors, ran WintoUSB ...... selected Win 10 ISO build 9879, selected the SSD drive, it went right to the select boot and sysetms partitions (I selected the same partition), it went right to installing...... 4 minutes later I copied Bootcamp 5.1.5621 to the drive. I then plugged it into my Mac Mini and booted right into Win 10, I then ran the Bootcamp setup for drivers and was done.. :cool:

Tried again, nope definitely doesn't work for me. That pic of the format was in Windows just to show the sector size, not attempting to format within WintoUSB.
 
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TPadden

macrumors 6502a
Oct 28, 2010
771
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Tried again, nope definitely doesn't work for me. That pic of the format was in Windows just to show the sector size, not attempting to format within WintoUSB.

All I can say is it definitely runs on my external NTFS 4K formatted 250GB 840 EVO Samsung SSD as well as 120GB OCZ Vertex 2 SSD in inateck SATA III UASP USB 3.0 enclosures without a hiccup, booting Windows 8.1 or Windows 10 to my MBA or Mac Mini :cool:.

Sorry I can't be more help.
 
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steve62388

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Apr 23, 2013
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All I can say is it definitely runs on my external NTFS 4K formatted 250GB 840 EVO Samsung SSD as well as 120GB OCZ Vertex 2 SSD in inateck SATA III UASP USB 3.0 enclosures without a hiccup, booting Windows 8.1 or Windows 10 to my MBA or Mac Mini :cool:.

Sorry I can't be more help.

I have looked into creating a Windows 2 Go installation to see if I can even get that working. Using Aomei Partition Assistant I attempted a Win2go install and came up with the error that the sector sizes of my Bootcamp partition and external disk did not match. So it's a similar error as WintoUSB.

That has got me thinking. How can I find the sector size on my Bootcamp partition, can I modify it with data intact, if I make a larger Bootcamp partition will it alter the sector sizes and what size would it have to be for 4k? My external drive is 4Gb in size.
 

TPadden

macrumors 6502a
Oct 28, 2010
771
452
I have looked into creating a Windows 2 Go installation to see if I can even get that working. Using Aomei Partition Assistant I attempted a Win2go install and came up with the error that the sector sizes of my Bootcamp partition and external disk did not match. So it's a similar error as WintoUSB.

That has got me thinking. How can I find the sector size on my Bootcamp partition, can I modify it with data intact, if I make a larger Bootcamp partition will it alter the sector sizes and what size would it have to be for 4k? My external drive is 4Gb in size.

Sorry, I'm a little confused in what you are trying to do. It sounds like you are trying to clone or move an internal operating Bootcamp partition to a bootable external drive, not do a fresh Windows install to an external drive that will boot on a Mac??????

For the latter, which is what I did, Bootcamp is just the term used for the driver folder downloaded from Apple.
 
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steve62388

macrumors 68040
Apr 23, 2013
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Sorry, I'm a little confused in what you are trying to do. It sounds like you are trying to clone or move an internal operating Bootcamp partition to a bootable external drive, not do a fresh Windows install to an external drive that will boot on a Mac??????

For the latter, which is what I did, Bootcamp is just the term used for the driver folder downloaded from Apple.

Trying to move a Bootcamp partition to a bootable external drive. I thought I would give Win2go to see what it would do.

I might be onto something with the sector sizes. I have been looking at all sorts of different programs to get this working and I stumbled across this:-
http://drbl.org/faq/fine-print.php?path=./2_System/103_wd_advanced_format_disk_clone.faq#103_wd_advanced_format_disk_clone.faq

I think a step forward might be to get the sector sizes to match, but I'm not sure that is possible. The Bootcamp partition is set at 512. My 4TB drive cannot be formatted at 512 (I tried manually overriding via FORMAT command), error message says it is not supported. So my only option is to somehow specify the size on the Bootcamp partition as 4k.
 
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