Speeding Up Mail

Large quantities of e-mail can clog up your system really fast. When in your opinion Mail is running slowly try one of the following solutions:

How To Speed Up My Mail

If you follow these tips, you’ll speed up Mail immensely:

  • Clean out regularly your Inbox and your Sent folder. Delete all unnecessary messages, don’t keep hundreds of them in your Inbox if you don’t need these letters.
  • Archive the messages. Archiving them is usually useful if you have messages on a server. Create a new mailbox (you can call it Archive) and drag messages there from a Mailbox. To create the new mailbox, choose Mailbox – New Mailbox.
  • Split Mailboxes. Sometimes you’ll need to keep hundreds of messages in your Mailbox. Why not to create two mailboxes and split messages accordingly?
  • Check for the new messages less frequently. Indeed, checking your Mail less frequently enables the system to perform faster. Choose Mail – Preferences. Then click General. Use the Check for New Messages drop-down menu to check for email every hour or so.
  • Remove recipients: By default, Mail will remember every e-mail address you enter. After a while, this gets clunky. Choose Window – Previous Recipients. Now highlight any recipients you don’t need anymore. Click Remove from List.

Speed: IMAP versus POP

Two main types of e-mail system exist. That’s Internet Message Access Protocol (IMAP, for short) and POP (Post Office Protocol). When IMAP is used, all e-mails are stored remotely on the server (some exceptions apply). On POP, the messages are downloaded from the server and stored on your computer (also with few exceptions).

Using POP, you have a speed advantage, as once the messages are downloaded, they can be downloaded instantly. IMAP, on the contrary, depends on how fast your server and network are running. IMAP is very useful, when you need to access your e-mail from more than one device. In this case, the messages are synchronized across iPads, iMacs, iPhones, Apple Watches, MacBooks and so on.

Check also our text How to Speed Up Applications.

What to Do if Your Mail Runs Slowly

If your mail runs slowly, you can do the following (Please test after taking each of the following steps that you haven’t already tried, before you proceed. Stop when the problem is resolved). Don’t forget to back up all data before making any changes.

Step 1: If you use iCloud Drive, open the iCloud pane in System Preferences. There is a checkbox marked iCloud Drive. Next to that, you’ll see a button marked Options. Click that button. In the sheet that drops down, uncheck the box marked Mail if it’s checked.

Note that this Mail checkbox is not to be confused with the another one, also marked Mail, that appears when you first open the iCloud preference pane. They have different effects.

Step 2: (If Mail still won’t launch, or if you can’t take this step for any other reason, skip to Step 3.) As we explained above, there are three types of mail account: IMAP, Exchange, and POP. You can determine the type of each account by opening the Mail preferences window, selecting the Accounts tab, and then selecting Account Information. Export all POP mailboxes to the Desktop folder. If you have IMAP or Exchange accounts, and you don’t store sent, deleted, and junk messages on the server, export those mailboxes the same way. You can determine whether the messages are on the server by selecting Mailbox Behaviors in the Accounts tab. Also export all mailboxes in the On My Mac category. You don’t have to export the other mailboxes, because the messages are stored on the servers. Quit Mail.

Step 3: In System Preferences, open Internet Accounts (OS X 10.9 or later) or Mail, Contacts & Calendars (OS X 10.7 or 10.8). Make notes of the settings for each mail account (all types), then delete the accounts.

Step 4: Quit Mail if it’s running. In the Finder, hold down the option key and select Go – Library from the menu bar. Move the following items (but note that some of them may not exist) from the folder that opens to the Desktop: Application Support/AddressBook/MailRecents-v4.abcdmr

Important note: you are not moving the Mail application. You’re moving a folder named “Mail.”

Step 5: Now launch Mail. It will behave as if you were setting it up for the first time. Go through the setup process with one account, using the information from Step 3. Test. If Mail works now, recreate the rest of the accounts (if you have more than one) and other settings. Any custom stationery that you created may be lost. Ask for instructions if you want to preserve that data. If there’s no improvement, quit Mail and put back the items you moved to the Desktop, replacing any newer ones that may have been created in their place. Stop here and post your results.

Step 6 If you took Step 2, import the mailboxes you exported (see the support article linked to Step 2 for instructions.) Typically, the process takes a few minutes, but it may take hours if you have gigantic mailboxes. In that case, you may be able to speed things up by temporarily adding your home folder to the Privacy list in the Spotlight preference pane. Remove it when Mail has finished importing. The mailboxes that you didn’t export should synchronize automatically with the server. Again, if the mailboxes are very large, downloading them may take quite some time, and network performance will be slower than usual during that time. If you skipped Step 2, look inside the Mail folder on the Desktop for a subfolder V3/Mailboxes (for OS X 10.11 or later) or V2/Mailboxes (for any older version of OS X). Import the mailboxes it contains and test. If Mail is still working, delete the items you moved to the Desktop in Step 4. Re-enable the Mail option in the settings for iCloud Drive, if you disabled it, and test again. If you weren’t already using iCloud Drive with Mail, there is no need to enable it now, unless you want to.


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This post currently has one response

  • Hi,
    I had over 37,000 in my mailbox. I received warning that I needed to “Buy more Storage”. Mail was using over 3.1G of space. So, I naturally decided to delete all those old emails (since March 2020).
    For days I have been trying to gain more space in Apple Mail. I have waited for hours as the mail moved itself somewhere. I went to bed x 2.
    Today I began early, with the remainder 21,000 emails to delete. I read up on making space on Apple (HTG) and opened the Mail in Library. It had 5.78GB stored. I then compressed this box, making zip file.
    As I was compressing, I noticed the deleting files sped up from one second to zoom speed. Happy days! However, Mail in preference still shows mail taking up 3G of space.
    I want to know why compression of the mail in Library made such a change?
    Why is my iCloud mail still showing 3G storage taken? (blue line)
    Also, I found that I have buckets of storage in my delightful and beautiful iMac Retina 27″ (A dream for me) If I can get a screwdriver into it and follow all the instructions I found online.
    Question 2: Why doesn’t Apple plug in these storage clips (little blocks) before selling the product? I had no idea there is 8G of totally wasted space and here I am struggling to reduce items to make more space. Also, should this be carried out by a technician? It is beyond rationale for me. Thank you for all this valuable information above. Very helpful for those of us who are dogs with a bone (me).

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