The Personal Folders Backup add-in creates backup copies of your .PST files at regular intervals making it easy to keep all of your Outlook folders safely backed up.
Although the download site states that it only works with Outlook 2002, 2003 and 2007, it can actually be made compatible with Outlook 2010 as well with a Registry.
Unfortunately it can’t be made compatible anymore with Outlook 2013, 2016 and 2019, nor can it with Office 365. However, for these versions, alternatives are available as well.
Continue reading: Microsoft Outlook Backup Add-in not available