I have an 8GB USB drive and want to use Ventoy to store both a Windows 11 installer and a Linux distribution. The Windows 11 ISO nearly fills the drive by itself, leaving no room for anything else. What are the practical ways to reduce the ISO as much as possible? I've heard about converting install.wim to install.esd with DISM or wimlib, but I'm not sure which provides the best compression. Can removing unused Windows editions or other components reduce the image further?
2 Answers
You can also replace install.wim with a more highly compressed install.esd using DISM or wimlib, but the amount saved depends on the image and its editions. Removing editions first usually makes the biggest difference; aggressive component removal can break servicing, updates, or installation features, so it’s best tested carefully. If the goal is simply to keep multiple installers on the drive, using a 16GB or 32GB USB stick is generally safer and far less work.
A practical approach is to remove the Windows editions you don’t need from the installation image. Tools such as NTLite can remove editions like Home, Education, Single Language, and Workstations while leaving only the version you plan to install. One example reduced a Windows 11 IoT LTSC ISO from about 6.38GB to 4.35GB.
Is removing unused editions the main option, or are there other worthwhile ways to reduce it further?
There is also a FAT32 limitation: a standard Windows image can contain files larger than 4GB, while some systems may not boot an NTFS installer. Trimming the image can help in that specific situation, but an untouched 8GB drive is usually too restrictive for a Windows installer plus another operating system.