How do I cancel the transfer after it has started?
It's easy on the PC side, because there is a cancel transfer button. But the Mac is stuck still displaying "copying owners Music". With no way to terminate this window. How do I stop it?
MacBook Pro
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If you cancelled the transfer in your PC, just close the Migration Assistant window in your Mac or, if you are using Setup Assistant, turn off the Mac holding the Power button.
If you can't close the Migration Assistant window, open > Force Quit, and quit that window. And if nothing works, go to > Restart, or turn off the Mac holding the Power button