Hi @Dany H ,
Welcome to our forum!
How did you export your mailbox?
And what's your account?
Please refer to this official article to export your data:
Export emails, contacts, and calendar items to Outlook using a .pst file
Please note:
And then when you start exporting, please *Make sure that the Include subfolders check box is selected. This ensures that everything in the account will be exported: Inbox, Calendar, Contacts, and Tasks. Choose Next.
*
Hope to help you!
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