If I bought an official retail USB key of Windows 10, can I use it as-is in Boot Camp Assistant or do I need to make a new key from a downloaded .iso?
A question on Super User prompted me to try research this, but Apple's Boot Camp instructions are somewhat confusing...
From Apple KB : How to install Windows using Boot Camp
2. Get a Windows disk image
When you purchase Windows, it comes as a disk image file (ISO) that you download, or as an installation disc or USB flash drive. If your copy of Windows came on a DVD, you might need to create a disk image of it to work with Boot Camp. If your version of Windows came on a USB flash drive, you can download an ISO from Microsoft.
OK, deep breath...
Does that actually mean that if someone went to the trouble of going to a real store & buying a real copy of Windows 10, in a box, with a USB installer & serial number on a card - that all they really gained was a serial number on a card & they still have to go through the process of making their own USB stick from a downloaded .iso?
If you follow Apple's KB trail to try figure this out, this is what happens...
You start from Apple KB : How to install Windows using Boot Camp & click the link at
- Use Boot Camp Assistant to install a new copy of Windows.
which takes you to How to install Windows using Boot Camp, my opening gambit from above & the link
you might need to create a disk image
which takes you to Create an ISO image for Boot Camp from Windows installation media
the second paragraph of which states...
If your copy of Windows came on a USB flash drive, see Use Windows 10 on your Mac with Boot Camp for more information.
...which takes you right back to where you started, ready to go round again...