Boot Windows from external USB with 13" Macbook Pro Broadwell

[davidb02]

How do I boot from an external USB device on a Macbook pro running OS-X Sierra?

Unfortunately, I am new to Macs & OS-X, so am not sure how things work.

I am trying to boot from an external USB drive containing Windows 10 on my Macbook pro running OS-X Sierra. However, when I start the system and hold the option key only the internal disk is shown and the option to net boot, no USB device is shown. The external USB drive boots successfully from a Linux PC and a Windows laptops.

 

[Toutou]

How did you create the USB drive? Are you trying to boot a "to go" version of Windows, or an installation?

 

[davidb02]

The USB drive has a complete installation of Windows 10, which boots successfully on a Linux PC.

Also, when I connect the drive after booting into OS-X, it doesn't appear most times, but when it does sometimes the message unable to read while on other occasions it can see the files on the disk. I thought maybe the drive or ports are iffy. However, this doesn't happen when I connect other USB drives or when I connect the external USB drive windows to a Linux or Windows system.