If you want to Import IMAP folders in Outlook to all emails but you don't know the best way to do this task. Here I suggest you the best tool eSoftTools IMAP Backup and Migration Software for doing this task in a simple manner. You can use this tool to download all your emails from the roundcube account. This tool easily exports your emails into various file formats- EML, EMLX, PST, HTML, MHTML, MSG, MBOX, PDF and more. 

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