Archiving E-Mail in Mail
From Mac Guides
After a while, Mail may accumulate large numbers of emails, causing performance hit, or lots of bad matches in Spotlight. This guide provides several methods of archiving.
Archiving Folders in Mail
- Select the folder from the source list on the left of Mail. For example, the Inbox, or any special folder you have created.
- Drag it to the desktop. This will create a mbox folder.
- If space is an issue, control-click on this new folder and select "Create Archive of 'Inbox.mbox'".
- Delete the messages from Mail, to reclaim the space and make Mail more responsive.
Use File > Import Mailboxes from within Mail to retrieve the messages (which are still searchable by Spotlight, unless they've been archived).
Use an Off-site E-Mail Account
Many independent email providers provide ample space. Saving a copy of every email to this remote site mean an email does not have to be stored locally forever.
- Sign up for an email account somewhere that provides plenty of space, such as Gmail.
- Create a rule in Mail by opening Mail's preference window and selecting the Rules tab.
- Set up the rule to read as follows
If any of the following conditions are met: Every Message Perform the following actions: Forward Message to email@example.com
This rule would make Mail forward your messages to the selected email account. Some people may not prefer this because forwarding mails causes your destination email account would now have all mails addressed from you (to you) and you'd have to open each mail to know who the actual sender and recipients were (since it's impossible to guess correctly just from the subject). If you'd like to have it resemble the original mail, you could instead "redirect" instead of "forwarding" - this would retain the same sender/recipients as the original message and yet get forwarded to the selected account. To accomplish this, use the following rule
If any of the following conditions are met: Every Message Perform the following actions: Redirect Message to firstname.lastname@example.org
- Assign a helpful description ("Forward to gmail") and save the rule.
- Position the new rule so it is below the junk filter(s). This rule stops evaluating rules when it has a positive match, which is desirable, since there is no need to send spam off to the remote email account.
Archive the Entire Mail Library
It is also possible to archive Mail's entire library at once. This may be desirable when upgrading to a new Mac for example.
- Quit Mail.
- Navigate to ~/Library
- Control-click on the Mail folder and select "Create Archive of Mail"
- This will create Mail.zip which you may offload to a backup device.
To use this archive, quit Mail, remove (or rename) ~/Library/Mail and unarchive the .zip file to this location.