If you can't see the 'Next' button while installing Windows on your iMac (Retina 4K, 21.5-inch, Late 2015)
If you're installing Windows 10 on an iMac (Retina 4K, 21.5-inch, Late 2015), you can use keyboard shortcuts to progress through the Windows installer if some parts of the window appear offscreen.
During installation, you might not see the Next button on the language and input screen of the Windows Setup application. Use these steps to go to the next screen:
Use the pointer to select the language, time, and currency format and your keyboard or input method.
Press Alt-N to go to the next screen.
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