Backupify is described as 'is the only online data backup and storage provider that enables users to backup their cloud accounts seamlessly to the Amazon S3 cloud, which has a great security and data duplication policy' and is an website in the Backup & Sync category. There are more than 10 alternatives to Backupify, not only websites but also apps for a variety of platforms, including Windows, Linux, Mac and iPhone. The best alternative is MailStore. It's not free, so if you're looking for a free alternative, you could try Gmvault or Piler. Other great sites and apps similar to Backupify are Keepit (Paid), SysCloud (Paid), Spanning (Paid) and SpinBackup (Free Personal).
SysTools Office 365 Backup utility is meant for saving your Office 365 mailbox to PST. The utility helps you to export your emails, contacts, calendars from Office 365 account to Outlook mailbox to Outlook data file.
MailShelf Pro is a professional email archiving solution that covers all important aspects of a secure and compliant long-term archiving of your emails and which also offers you many additional features.