Install Windows on a partition of external hard drive

You can not install Windows using Bootcamp on an external drive.

I agree with Bob, but there is an alternative which works for me.

I recently replaced my HDD with an SSD. The HD has the original OSX partition, and the Boot Camp partition that was created when the HD was still in the MBP. Because I did not want to take up precious space on the SSD, I did not re-install BootCamp on the SSD.

Instead, I put the original HD in an external enclosure and use Parallels (I'm currently using a trial version; I'll be comparing it to the trial version of Fusion shortly).

Parallels sees the BootCamp partition on the external drive and runs it just as if it were a partition on the SSD.

My current MBP is only USB 2, but for what I do the read/write from the external drive is satisfactory. Once I pick up a newer MBP with USB 3, I expect a small increase in responsiveness.

BootCamp creates an MBR/NTFS emulation on the Mac drive (which has a GUID/HFS+ format) so Windows will be able to boot. And that can only be done on the internal drive.

If you are willing to sacrifice a wee bit of performance and don't need raw device access for whatever Windows software you plan to run, an alternative would be a virtual machine run on any of the virtualizers: Oracle VirtualBox 4 (free), VMware Fusion 5 ($50) or Parallels Desktop 8 ($80). As far as the Mac is concerned, the VM is just a big file and can reside anywhere you want.

No. You can not even install Windows on an external drive connected to a Windows PC. Use a virtual machine. Check the Prallels or Fusion sites for instructions regarding using virtual machines to install Windows.

Regarding "Thanks for your answers, but is it possible at all to install windows on a partition of an external drive?"

You could:

1. format your external drive "Mac" and install a bootable version of OSX on the external drive.

2. remove the external drive's HD and install it in your Mac (assuming it is 2.5" -- if 3.5", you'll have to have leave it outside the machine tethered to the SATA connector of the laptop).

3. boot the machine and install a BootCamp partition and Windows on the external (now effectively, "internal") HD.

4. put the drives back in their original locations.

5. boot the machine, use VM software to "see" the BootCamp partition on the external drive.

1. Have you tried this?

2. There are no external SATA connectors on Macs

Do it yourself, then post the method you used.

Yes. My late '08 Unibody MBP has a SATA connector in the internal drive bay. The cable was flexible enough to allow the drive to sit outside the chassis.

I just noticed the OP has a late '12 MBP, which I'm assuming does not have a separate SATA cable. 😟

MHN wrote:

Yes. My late '08 Unibody MBP has a SATA connector in the internal drive bay. The cable was flexible enough to allow the drive to sit outside the chassis.

Doesn't that make for a less convenient portable?

lol! It was dangling only long enough to do the format/install on the other drive.

I wonder...

Has either of you two bothered to READ the specs?

13" Late 2012 RETINA MacBook Pro.

In other words, NONREMOVABLE, NONREPLACEABLE storage device.

Currently we're discussing an 08 unibody, no use to the OP at all.

Oh, sorry. Forgot about the penchant here to go wildly offtopic, offspec, off the cliff.... 😝

Off with his head 😉

Happy to oblige...