Ten ISO files can take an entire evening to collect. The update will almost certainly leave them untouched - and the backup takes two minutes. Here is exactly what to copy, and what you can honestly skip.
This is the page nobody reads until the day they wish they had. Ventoy's Update mode genuinely preserves your data partition, and this guide will not pretend otherwise. But updates happen in the real world - with tired drives, loose ports and two very similar buttons in one window. A small, smart backup makes every one of those risks irrelevant. Here is the two-minute version, in the right priority order.
Let us be straight: Ventoy's Update mode is designed to preserve your data, and in normal use it does. So why back up at all? Because the realistic risks are not in the software's design - they are in the world around it. A pen drive that is quietly failing, a USB port that drops contact mid-write, a power cut in the wrong five seconds, or your own finger landing on Install instead of Update. A backup is not a comment on Ventoy; it is insurance against everything else.
ventoy folder, always. It sits on the data partition and holds ventoy.json, your theme files and plugin configuration. It is only a few megabytes, and it represents all your customisation work. Copy the whole folder to the PCdir in a command prompt and save the output. If the worst ever happens, this list is your re-download checklistMake one folder on the PC, named with the date - for example Ventoy Backup 2026-10 - and drop the copies inside. Keep it until you have booted the updated drive at least once and started an ISO successfully. After that, the small ventoy folder copy is worth keeping permanently; it is your theme and settings insurance for every future update too, and it costs almost no space.
Picture the common story: ten ISOs collected over an evening - installers, rescue tools, three Linux flavours - then one wrong click on Install during an update, and the evening is gone. Not because Ventoy failed, but because there was no copy. Two minutes of copying beforehand turns that story into a shrug: reinstall Ventoy, copy the files back, done. Technicians are not people who never make mistakes; they are people whose mistakes are cheap.
Watch the video first - then spend two minutes on this checklist before you press the Update button yourself.
Watch Full VideoBecause the risks are around the update, not inside it: a failing pen drive, a dropped USB connection, a power cut mid-write, or clicking Install by mistake. The backup is cheap insurance against all of them at once.
The small ventoy folder on the data partition. It holds ventoy.json, your themes and plugin settings - all your customisation - and it is only a few megabytes, so there is never a reason to skip it.
Only the irreplaceable ones, or all of them if this drive holds the only copies. Standard Windows and Linux ISOs can be re-downloaded quickly, so an honest backup is the ventoy folder, an ISO list, and the files that cost you real time to obtain.