We’re using a USB 3.0 drive, but a Thunderbolt drive should work as well. What You Need to Install Boot Camp on an External Drive Also, make sure you have a current backup before beginning. Be sure to read through the process before undertaking it. This is an advanced process with quite a few pitfalls that can trip you up. It allows you to install Windows on an external drive without first having Windows installed on a PC or in a virtual environment. But the method we’re going to outline here is a bit different. They range from creating clones of an existing PC installation or using Microsoft IT tools for installing Windows.

There are actually a few ways you can successfully install Windows on an external drive. Installing Windows on an external drive would be a great solution to the problem of available space, but as we said, Boot Camp and Windows impose a restriction on installing to an external drive. While Boot Camp Assistant can partition your startup drive for you to make room for Windows, there are bound to be many of you who just don’t have room to spare on your startup drive to install Windows. One of the downsides to Boot Camp and the Windows installer is that it restricts you to only installing Windows on your Mac’s internal drive. It’s a nice capability that lets you select – at boot time – which operating system you wish to use: macOS or Windows.

Boot Camp and Boot Camp Assistant allow you to install Windows on your Mac.

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