Hi @Dominik ,
Welcome to our forum!
In order to verify your issue, do you mean you want to find where the backup files are stored?
If in this case, you may follow the steps:
Go to click File > Account Settings > Account Settings, select Date Files tab.
Besides, you can also locate your pst-file in this dafaut location ** C:\Users\%username%\AppData\Local\Microsoft\Outlook\ ** (when searching for a pst-file, make sure you include hidden and system files and folders.)
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