Create a bootable USB drive for Windows Server

The Windows Server image contains a .wim file which is bigger than 4GB. This is a problem because FAT32 does not support files bigger than 4GB. To solve this problem, we need to split the .wim file into smaller files. This can be done with the dism command. The following script extracts the content of the ISO file, splits the .wim file, formats the USB drive, and copies the files to the USB drive.

# TODO must be run as administrator
# TODO configure both the ISO file path and the USB drive

$ErrorActionPreference = "Stop"
$PSNativeCommandUseErrorActionPreference = $true

$IsoFile = Resolve-Path "en-us_windows_server_x64_dvd.iso"
$UsbDrive = Get-Disk | Where-Object BusType -eq "USB"

# Check if the USB drive is found
if ($null -eq $UsbDrive) {
    throw "No USB drive found"
}

# Extract the ISO to a temporary folder
$TempFolderPath = Join-Path $env:temp ([System.Guid]::NewGuid())
$TempFolder = New-Item -Path $TempFolderPath -ItemType Directory
$DiskImage = Mount-DiskImage -ImagePath $IsoFile -StorageType ISO -PassThru -NoDriveLetter
New-PSDrive -Name ISOFile -PSProvider FileSystem -Root (Get-Volume -DiskImage $DiskImage).UniqueId
try {
    Get-ChildItem "ISOFILE:" | Copy-Item -Destination $TempFolder -Recurse

    # Split the wim file into multiple 4GB files, so that it can be copied to a FAT32 drive
    dism /Split-Image "/ImageFile:$TempFolderPath\sources\install.wim" "/SWMFile:$TempFolderPath\sources\install.swm" /FileSize:4096
    Remove-Item -LiteralPath $TempFolderPath\sources\install.wim -Force

    # Format the USB drive to FAT32
    $UsbDrive | Clear-Disk -RemoveData -Confirm:$true -PassThru
    $UsbDrive | Set-Disk -PartitionStyle GPT
    $Volume = $UsbDrive | New-Partition -Size 8GB -AssignDriveLetter | Format-Volume -FileSystem FAT32 -NewFileSystemLabel WS2022

    # Copy Files to the USB drive
    Copy-Item -Path $TempFolderPath\* -Destination ($Volume.DriveLetter + ":\") -Recurse
}
finally {
    # Cleanup
    Remove-PSDrive -Name ISOFile
    Dismount-DiskImage -DevicePath $DiskImage.DevicePath
    $TempFolder | Remove-Item -Recurse -Force
}

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