Hi @Allan Fernandes ,
Welcome to our forum.
If my customer wants to backup their O365 outlook data to PST 's on Premise (Local HDD)
As I know, for your requirement, we actually could back up our data via exporting a pst file directly in Outlook desktop client. Here are detailed steps:
File> Open & Export> Import/Export> Export to a file> Outlook data file(.pst)>choose the data that you would like to export>Browse the location>Finish
Hope that would be helpful to you. If your issue has any update, please feel free to post back.
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