To do this, it does the following operations: When Windows 10 is installed with Boot Camp Assistant, Boot Camp Assistant prepares the disk for installation. I have seen it a lot, since I do testing with ISO of Windows Enterprise downloaded from Microsoft that have been showing this problem. It didn’t seem to happen with all ISO so I investigated the issue, filed a bug with Apple, and figured out a workaround to the problem. In the last few months, people installing Windows on their Macs with Boot Camp Assistant have started seeing the message “An Error occurred while copying the Windows installation files” when using some Windows 10 ISO downloaded from Microsoft. WE HAVE LEFT THIS ARTICLE AND THE DOWNLOAD FOR HISTORICAL PURPOSES. NOTE: THIS UTILITY SHOULD NO LONGER BE NEEDED DUE TO APPLE UPDATING BOOT CAMP ASSISTANT TO USE EXFAT.