Hi @Fondacio France ,
Welcome to our forum!
What's your account? (Exchange online/Outlook.com/Microsoft 365/Exchange, etc)
How did you archive messages in Outlook? Archive older items manually in Outlook for Windowsor something else?
If you archived older items manually, we can find the archived .pst file under the path we chose when archiving.
If you're using a Microsoft 365, Exchange, Exchange Online, or Outlook.com account, you cannot change the location to which your archived items are moved. The Archive folder is one of Outlook's default system folders.
If your organization enabled online archive for you, a user’s Online Archive acts somewhat like a second account in Outlook with its own folder structure. Therefore, it isn’t included in searches performed from the Inbox.
Hope to help you!
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