synchronisation Lightroom

This is confusing. What do you mean by "Lightroom Classic in the cloud"??? There is no such thing. If you are talking about some software running on your local computer, please tell us the exact name and version NUMBER (we need the version NUMBER and not words like "latest" or "up-to-date")

in the future, to find the best place to post your message, use the list here, https://community.adobe.com/

p.s. i don't think the adobe website, and forums in particular, are easy to navigate, so don't spend a lot of time searching that forum list. do your best and we'll move the post (like this one has already been moved) if it helps you get responses.

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