The 3-2-1 backup rule, applied to your email
Three copies, two kinds of storage, one off-site. How to apply the 3-2-1 backup rule to Gmail, Outlook or your hosting email without overthinking it.
Blog
Notes on keeping your email
How to back up email properly, why open formats matter, and what changes in Arca Mail Backup.
Back Up Outlook.com and Microsoft 365 Without PST Files
How to back up Outlook.com, Hotmail or Microsoft 365 without relying on PST: the PST's limits, IMAP with Microsoft sign-in, and an open mbox format.
Arca Mail Backup vs. Mail Backup X: an honest comparison
Mail Backup X backs up IMAP accounts and desktop mail apps on Mac and Windows. Arca saves open mbox files, to NAS or S3 too. How they differ and which to pick.
What Is an mbox File, and Why an Open Format Matters
An mbox file stores many emails in one plain-text file. What's inside, which apps open it, and why the format matters when you're keeping a backup.
Google Takeout vs. Automatic Backup: Which One for Gmail?
Google Takeout exports your Gmail as mbox, but it's a snapshot. How it differs from an automatic IMAP backup, and when each one makes sense.
How to Back Up Gmail to Your Computer (2026 Guide)
Step-by-step: back up Gmail to your own drive with 2-Step Verification, an app password and IMAP, plus how to handle All Mail, labels, Trash and Spam.
Your Email Is in the Cloud. That Isn't a Backup.
Gmail and Outlook keep your mail running, but they won't save you from a deletion, a closed account or a hijacked login. Here's where your own backup comes in.
Out now on Windows and Mac
Start with one account, free.
Arca Mail Backup is in the Microsoft Store and the Mac App Store. It's free for one account, and Arca Pro adds more accounts, NAS and S3 storage. Arca Pro is on sale now in both stores.
Windows
Windows 10 version 1809 or later, or Windows 11
Mac
macOS 14 or later
