Once the old Windows version is installed, you can use the integrated Windows updater to install the most recent version. The files however are still coming from Microsoft directly, so there is nothing to worry about. The website gives us access to previous Windows releases. Therefore you need to download an older version of Windows 10 from an alternative source.

The ISOs provided by Microsoft contain files that exceed that limit. But files in FAT32 are limited to a maximum size of 4 GB. On macOS you are forced to use the FAT32 filesystem for your thumb drive, because NTFS is not supported by macOS and ExFAT is probably not supported by your BIOS. Microsoft offers official downloads for Windows ISOs, but unfortunately you can not use them. You are now ready to boot Windows 10! Why is an old Windows ISO file necessary? When this is done you can eject the USB stick. The copy process may take a little while, depending on the speed of your thumb drive. Now copy all files to your USB drive (e.g.

I believe you can install the language pack of your choice later on then. If you don’t find a download for your language, give the German version a try. You will get to see the cryptic “SHA1” key on the right which you can use to easily search the web for alternative download sources.įor the German version, for instance, the SHA1 key is “537f817703323d28f673b4e36e377919e1ee034e” from which I found this download from “ComputerBase”. If you get stuck here please try to use the website’s search function on the top, search for “Windows 10, Version 1803 (Updated Apr 2018) (圆4)”. Warning It looks like this step is no longer working adequately, because the described ISO images are not available for download anymore. Finally click “Download” and continue with the next step in the meantime. Go to and select “Windows (Final)” as type, “Windows 10, Version 1803 - Redstone 4 (build 17134.1)” as version (do not select a more recent version), “Windows 10” as edition, a language of your choice and finally the file that ends on “_圆4.iso” if you don’t know any better. If you want to find out why this is necessary please refer to the section on the bottom of this article. In this step you have to download a rather old version of Windows 10. All the data on the USB drive will be lost in the process, so make sure to save the data elsewhere before you continue. You need a USB stick with a capacity of 8 GB or more. The instructions are absolutely foolproof, no terminal is required and the resulting USB drive can be used to install Windows on any machine and is not limited to “Boot Camp”. This tutorial explains how to create a bootable Windows USB in macOS without any additional tools.

Booting imac from usb