If you only need a one-time backup, using Outlook with IMAP and exporting to a PST file works, but it can be a bit time-consuming. For larger mailboxes or if you want more export options like PST, MBOX, or PDF, a dedicated backup tool can definitely make the process easier. No matter which method you choose, it's always a good idea to keep an offline backup of important emails on a USB drive or external hard disk.