Split install.wim into install.swm and install2.swm

sources\install.wim in recent releases of Windows 10 has exceeded FAT32’s maximum filesize of 4 GiB. If you only boot UEFI systems and you want to use memory sticks for better performance while installing, you must split sources\install.wim into smaller files. Luckily, the dism command can do this for you.

1. Start by creating a new temporary directory, say C:\W10-EN-20H2-splitted.
2. Mount your .iso file in a virtual DVD drive by doubleclicking the file in Windows’ File Explorer.
3. Copy all files and directories from the virtual DVD drive to the temporary directory.
4. Launch cmd.exe with elevated privileges, e.g. Win+R, type in cmd, and hit this key combination Ctrl+Shift+Enter.
5. Enter c: and hit the enter key.
6. Enter cd \W10-EN-20H2-splitted\sources and hit the enter key.
7. Enter dism /Split-Image /ImageFile:install.wim /SWMFile:install.swm /FileSize:4095 and hit the enter key. This will create the two files install.swm and install2.swm. Additional files might be created for future releases of Windows 10.
8. Enter del install.wim and hit the enter key.
9. Enter exit and hit the enter key.
10. Use ImgBurn or your favorite tool for creating .iso files and create a new .iso file for this new distribution. Ensure you only include the contents of the C:\W10-EN-20H2-splitted directory.
11. Use Rufus or your favorite tool for creating bootable memory sticks and point it to the newly created .iso file. You’ll notice Rufus now allow us to use FAT32 as the main filesystem, and not only NTFS.
12. Delete the temporary directory created in step 1 at your own discretion.