Mail terribly slow after upgrading to Yosemite

Quit Mail if it's running. This procedure will have no effect unless you quit Mail when you begin.

Back up all data.

Triple-click anywhere in the line below on this page to select it:

sqlite3 L*/C*/*.mail/*/L*/*/*/C*.db vacuum; sqlite3 L*/M*/*/*/E*ex vacuum

Copy the selected text to the Clipboard by pressing the key combination command-C.

Launch the built-in Terminal application in any of the following ways:

☞ Enter the first few letters of its name into a Spotlight search. Select it in the results (it should be at the top.)

☞ In the Finder, select Go ▹ Utilities from the menu bar, or press the key combination shift-command-U. The application is in the folder that opens.

☞ Open LaunchPad. Click Utilities, then Terminal in the icon grid.

Paste into the Terminal window (command-V).

You should see a new line ending in a dollar sign ($) appear below what you entered. If not, press return. You can then quit Terminal and relaunch Mail. Test.

Please follow these directions to delete the Mail "sandbox" folders. In OS X 10.9 there are two sandboxes, while in 10.8 there is only one. If you're running a version older than 10.8, this comment isn't applicable.

Back up all data.

Triple-click anywhere in the line below on this page to select it:

~/Library/Containers/com.apple.mail

Right-click or control-click the highlighted line and select

Services ▹ Reveal

from the contextual menu.* A Finder window should open with a folder named "com.apple.mail" selected. If it does, move the selected folder—not just its contents—to the Desktop. Leave the Finder window open for now.

Log out and log back in. Launch Mail and test. If the problem is resolved, you may have to recreate some of your Mail settings. You can then delete the folder you moved and close the Finder window.

Important: This action will delete any custom Mail stationery that you created. If you want to preserve that data, ask for instructions.

If you still have the problem, quit Mail again and put the folder back where it was, overwriting the one that may have been created in its place. Repeat with this line:

~/Library/Containers/com.apple.MailServiceAgent

Caution: If you change any of the contents of the sandbox, but leave the folder itself in place, Mail may crash or not launch at all. Deleting the whole sandbox will cause it to be rebuilt automatically.

*If you don't see the contextual menu item, copy the selected text to the Clipboard by pressing the key combination command-C. In the Finder, select

Go ▹ Go to Folder...

from the menu bar and paste into the box that opens by pressing command-V. You won't see what you pasted because a line break is included. Press return.

Thanks works much better now ... get back on normal speed.

Genius! Linc, thank you SOOO much. Your method made mail work properly again. Thank you!!

--Emily

So that totally worked, thanks Linc. But could you make a moment to explain why? I see that folder was a little bloated with attachments, but all my attachments seem to still also be in my email. From where? And why were they copied in that folder?

Note for 10.10.3 upgrade for those experiencing slow mail, mail beachball, etc. The SECOND response by Link Davis seems to have solved my Mail.app problems.

Just updated to Yosemite 10.10.3 and Mail was extremely slow. Switching between messages was slow, switching between mailboxes was slow, sometimes there was even a lag as I was typing a message.

Removing the folder identified by Link Davis, logging out and logging back in, and starting mail again seems to have fixed my slow Mail.app problem.

I tried many other solutions before finding this one. I removed plists, deleted hundreds of old emails, vacuumed the database, of course fixed permissions, fixed disk in safe mode, etc., etc.

After moving the directory ~/Library/Containers/com.apple.mail out and logging back in, mail is back to "snappy"...Just as I finished downloading a different email app. phew.

After moving the directory ~/Library/Containers/com.apple.mail out and logging back in, mail is back to "snappy"...Just as I finished downloading a different email app. phew.

What happens to Mail when you move the above file to desktop? Settings, accounts, signatures etc erased? And I have to re-add everything?

Also once file moved to desktop, safe to delete?

wow this fixed the problem thanks

The Mail account “” is shared by other applications on this Mac.

Linc I am trying to remove my iCloud account from Mail but get the following error. I have Mail not selected in iCloud settings on Mac. I want the account removed from the Accounts preferences pane in Mail but can't remove it.

Any ideas?

I tried the procedure to move ~/Library/Containers/com.apple.mail to the Desktop. When I restarted Mail, all preferences were reset to their defaults. In trying to change them back to what they were, no changes actually "took" -- any change that I made to preferences were not saved when I closed the preferences window. There were other oddities to, such as being unable to uncheck the "Enable Junk Mail" option -- when I clicked on the checkbox to turn that off, it turned itself right back on again.

Following Mr. Davis' instructions to remove the newly-created com.apple.mail folder and replace it with the old one that I had previously dragged to the desktop seemed to get me back to "normal" with Mail ("normal" = very slow performance since 10.10.3 upgrade).

Once you move the com.apple.mail folder to desktop reboot your Mac. Then open Mail. Then all preferences you set will remain intact.

And yes I agree. There has been a slight improvement but 10.10.3 still has Mail running very slowly with Google accounts.

OK, I tried it again and it still lost some of my preferences (as Linc Davis indicated), but this time they could be changed back. The Preferences>Accounts settings stayed the same, as did Signatures and Rules, but the rest of the preferences were reset. Also had to change some of the preferences under the "View" menu.

And, there does seem to be some improvement.

Having used mail for many years, I am very aware that it has this ridiculous need to sync and re-sync to the server, over and over again. In the activity window, you can watch it do so for every one of your mailboxes, even ones that haven't been touched in six months. For many years, Apple Mail has gotten clogged up with this continuous re-syncing, which means that other tasks it needs to do get delayed. Restarting Mail usually helps for an hour or a day, and then it gets bogged down again. It had actually seemed to get better with Yosemite, but 10.10.3 was a step back. With Linc Davis' fix, at least it stops re-syncing once it syncs all mailboxes, rather than just doing it over and over. However, when I do even the smallest task in Mail, such as a search, it still initiates a resync of all mailboxes, even after Linc Davis' fix, although it now stops after it's done.

I'm guessing that this probably mostly affects those of us who are e-mail pack-rats, of which I am a charter member, having about 600,000 messages on file. Those with much smaller mailboxes probably won't notice this annoying behavior.

Anyway, thanks to everyone who contributed solutions, as this was helpful.

Thank you Linc I can not even begin to express how this has helped me. I spent the whole weekend trying to resolve my issues and this worked instantly. THANK YOU.