JFlowOS 1.0 is a direct download. Newer releases are activated with assisted installation: you verify your email and the JFlowOS technical and sales team contacts you to continue.
With balenaEtcher, Ventoy or «JFlow Live-USB Maker».
Connect it to the internet (cable or Wi-Fi from the network icon).
JFlowOS finds your installation and updates it without erasing files, users or programs.
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Pick a release above. If you don't pick one, you request the latest.