What is the best way to back up am IMAP mail account on a Mac?

April 21, 2022 3:11 PM

I've been using dreamhost for over 20 years as a hosting service so I have personalized email. I'm up against my storage limits and would like to download attachments and delete them from the server while keeping the mail. I'm OK with keeping the mail offline if necessary but I have no idea how to do this effectively as the host doesn't allow for smart mailboxes online. I can only do those locally. Perhaps I should create a smart mailbox locally, then drag those files into a sever based folder then archive the whole mailbox? Any better suggestions? Thanks.
posted by captainscared to Computers & Internet (4 answers total)

One strategy is use the mail client Thunderbird and set up POP for your email account on it. Then download (POP off) all the your email. Then you can go in via an IMAP client and delete email and remove attachments leaving your Thunderbird archive intact.
posted by rmmcclay at 10:53 PM on April 21, 2022

If you're OK with keeping the mail offline... When I've been up against IMAP limits I've used the Mail app on my Mac to create mailboxes under the "On My Mac" section, in the mailbox listing on the left. Then dragged messages from an IMAP folder into the new "On My Mac" folder. The messages will be moved rather than copied. If you want to copy them, hold the option key when you drag. Attachments seem to go with the messages too.

You might be able to drag entire mailboxes, rather than only the messages themselves - I'm just cautious and haven't tried that.
posted by fabius at 6:34 AM on April 22, 2022

Note that the mail on the server may not actually be deleted until you issue the formal delete command, which is the Mailbox/Erase Deleted Items... menu option (in Mail.app). You might try this first, to see if it frees up enough space.


I also recommend using Mail.app to drag mail to On My Mac folders.

In fact, I keep only one IMAP folder online (INBOX) - all the rest are On My Mac.


Also note that you probably have a gargantual SENT folder on the server, which you could delete, trim, or move to On My Mac depending on your goals.
posted by soylent00FF00 at 6:43 AM on April 22, 2022 [1 favorite]

It looks like the Mail app supports deleting attachments without deleting the message natively, though you'd likely need to do it one at a time if you use that client. If you don't want to move the entire message offline (e.g. because you use multiple email clients and want your email archive accessible to all of them), this appears to be an option that will do that for you.

Otherwise, I'd agree with the other answers that moving messages offline is probably the most straightforward and easiest approach. You might get in the habit of backing up and deleting attachments on messages as you receive them though.
posted by Aleyn at 11:20 AM on April 22, 2022