The native Windows format .wim (Windows Imaging Format) is large. Use the DISM command to convert it to .esd (Electronic Software Distribution), which is highly compressed:
Many compressed versions disable Windows Update or remove security patches to save space. Furthermore, official technical assistance and updates ended for Windows 8.1 in January 2023. windows 8 highly compressed
Instead of extracting Windows system files during installation, WIMBoot keeps them in a compressed Windows Imaging File Format (.wim). The native Windows format
DISM /Export-Image /SourceImageFile:"C:\Win8Source\sources\install.wim" /SourceIndex:1 /DestinationImageFile:"C:\Win8Compressed\install.esd" /Compress:recovery windows 8 highly compressed
