Hi @Lindy Jodie Anju DOMUN-MAZEN EXT ADM,
I was woundering if there is any third party tool that could be used?
From what I am aware of, there's no official recommended 3rd-party tools for your scenario. Given this, it's recommended to use the Import Service to migrate PST files.
Below is an article with detailed steps for reference:
(You can use machine translation to translate the content to English)
OVH Messaging Migration to O365
Please Note: Since the web site is not hosted by Microsoft, the link may change without notice. Microsoft does not guarantee the accuracy of this information.
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