Boot Camp error: An error occurred while copying the Windows installation files

I had the same issue very frustrating. i have a 2017 imac 27 and cant run windows on it after replacing the fusion drive with SSD drive.

This should be unrelated to Windows installation.

I dont understand what you mean. I am having the copying windows installation files in bootcamp error. Irregardless of what version of windows iso im using.

how do i copy all the contents from windows 10 iso file?

@Jangle28..You can use spotlight search or search the file in finder. Just double click the Windows ISO file and you should see multiple files in their.

Having been investigating this and coming to the the same conclusion as you it was a fat32 limitation problem tried your method and ir works. However I tried to modify it slightly so you don’t need a pen drive so I took the following steps.

create a new folder “left mine on desk top”

open boot camp assistant action menu Download windows support software

then save it to the folder created.

Then follow your steps 1-5

but also copy the content from the windows support software to osxreserved. BUT DO NOT COPY AutoUnattended.xml. Delete that file.

restart Mac and hold down alt. “ this can be tricky on new MacBook Pro’s as there is no chime. Press it down to early and it won’t be recognised press it to late and it boots in to Mac OS. “ if it boots into MacOS it deletes the partition osxreserved and you have to start again“ also after booting into the first screen of Windows setup I had to use a wired mouse as keyboard trackpad didn’t work. When windows started loading it worked OK.

then finish installing windows as per your instructions after windows installs go to drive D: osxreserved open folder bootcamp. select click setup.

After installation restart press option select MacOS then go to system preferences open select start up disk then select MacOS as your start up disk if asks if you want to restart select yes. ( if you don’t the default setting will be to boot into windows on restart) when you want to boot into windows start holding optio key and select windows.

I thought I might do that but I spent so many hours browsing internet and youtube so I had no patience for it anymore. Tomorrow on Sunday I will try to reinstall it. I will use April version of Windows 10 ISO file. And I will write what happened.

Yes it works! 1803 version of windows went without any problem. It only asked me for permission to process some changes(login and password). Then it did everything without me interfering.

In Windows it installed the drivers itself. But control for brightness does not work for me BUT SOUND sounds normal and great.

Thank you for contributions.

(MBP mid 2015 Ati gpu, Mojave 10.14.1, BootCamp Win 10_1803)

Use this download link for the Windows 10 ISO: https://www.microsoft.com/en-us/software-download/windows10ISO

Choose the April 2018 update from the drop down (which is 1803) then choose your language and confirm. The install.wim file in that ISO is 4.09GB since it contains home AND pro versions of Windows 10.

Thank you for this thread - I was banging my head against the wall trying to solve this one. My issue was I was using the 1709, 1803, and 1809 versions downloaded from VLSC which contain far more versions than just home & pro and the install.wim was entirely too large. Using retail ISO from Microsoft solved the issue.

I created a tool that helps with this issue was well if you want to use the latest Windows 10 ISO. The "an error occurred while copying the Windows installation files" issue is due to the install.wim file being too large in the ISO, and my tool splits it into smaller parts so it fits on a FAT32 filesystem.

The tool is free and you can read all about/download it here:

https://twocanoes.com/using-larger-windows-10-isos-with-boot-camp-assistant/

I created a tool that helps with this issue if you want to use the latest Windows 10 ISO. The "an error occurred while copying the Windows installation files"issue is due to the install.wim file being too large in the ISO, and my tool splits it into smaller parts so it fits on a FAT32 filesystem. 

The tool is free and you can read all about/download it here:

https://twocanoes.com/using-larger-windows-10-isos-with-boot-camp-assistant/

This doesn't work for me. I have isolated the issue as being specifically that my usb has to be formatted with fat(32) and neither the april nor the october release iso will fit specifically because of the install.wim file being too large. Nothing will copy them over when it is formatted for fat32. I have no problems when they are formatted with ExFat, but my pc does not recognize this format for booting purposes. It does recognize the fat32 format as I tried to boot from this minus the install.wim (since it is the only thing that won't copy over) and it gives me a missing file error.

This issue is resolved in the most recent mojave update.

Another option is to use the microsoft media creator. You have to be on Windows to use it (otherwise it just has you download the latest ISO):

https://support.microsoft.com/en-us/help/15088/windows-10-create-installation-media

tim

Ya, I’ve been trying to get a windows machine all day because that would make my life much easier. Went to UPS store and got kicked off their machine 3x in the middle of creating a boot stick, spent 20$ to get nothing accomplished.

About to say f it and go with Linux and make everything work from there. Seems easier at this point.

Total time building new pc...4 hours.

Total time trying to get Windows installed...12 and counting

Total time installing Windows 10 1803 on Sierra on a 2014 Mac (non-APFS macOS) - 1 hour. ;-)

(For everything else, there is a MasterCard/Visa/AmEx/Discover).

This did not quite work for me, but your observation regarding the file size in the October 2018 Update ISO is spot on. I am working with a late 2018 MacBook Pro, and OS 10.14. (I will not bore you with many permutations of attempts I made to get the October 2018 ISO to work, including the otherwise excellent advice given by evan-13. Creating bootable memory sticks, etc.) The short version of the story is that Boot Camp Assistant worked properly once I used the April 2018 Update ISO.