Mail is Slow and lagging.

Thank you very much Alf! This tip has perfectly solved my annoying slowness problem, especially the reindexing part:

(Excerpt from the cited Macpaw article, please read the full article to give credit).

"Reindex your Apple Mailbox

Rebuilding your Mailboxes is often enough to solve many of the issues an overburdened Mail app may experience. However, if you’re still having problems (such as the app becoming so unresponsive it barely works or fails to launch), you should manually reindex your Mailboxes.

Here’s how to manually reindex your Mailbox:

1. First, quit Apple Mail if the app is running.
2. Launch Finder and select Go from the Menu Bar.
3. Enter ~/Library/Mail/ and press Go.
4. Choose the V8 folder (depending on your macOS version, it can be named V5, V6, or V7) > MailData. Next, locate and delete all the files that start with Envelope Index, such as “Envelope Index” or “Envelope Index-wal.” 
5. Note: It’s a good idea to copy each file to your desktop before deleting it."

To continue the discussion, I'm a long-time Mac user and had very few problems with Mail and never had to rebuild any of my mailboxes until Big Sur macOS. The situation with Monterey is much worse and I'm continually rebuilding mailboxes. I finally tried re-indexing (https://macpaw.com/how-to/rebuild-mailbox-mac) recently and that fixed the problem. I suspect Mail problems will recur but at least it's stable for awhile. Using macOS 12.4 didn't resolve the problem and maybe even made it worse. Reinstalling macOS didn't help much either and problems keep recurring.

I had the same issue with my MacBook Pro, MacOS Monterey 12.6, Chip Apple M1 Max.

I had installed the GPG / Open PGP suite on my MacBook. When I started Apple Mail, every few times I would get a reminder to subscribe to the GPG Mail Extension. I always declined.

My MacBook Pro continuously got slower on start-up.

I uninstalled the GPG / Open PGP Extension and that fixed it.

Go to: Mail Preferences --> Extensions --> click on the Extension you want to remove and remove it. Close Mail. Reboot the computer.

My Apple Mail now loads normally. This may be affected by any Extension and not limited to just the GPG / Open PGP Extension. You may want to remove all Extensions.

I am relieved to have fixed this issue on my 2017 iMac (after chasing down all of the other rabbit holes). Evidently something was corrupted in my user account; this problem went away when I created a new user account and deleted my old user account. Mail, Reminders, and Calendar are now quick and responsive.

After a few months of dealing with this myself I found a fix, that worked for me. I copied this from a site I found and have since lost the link to, so I apologize to the originator of this information. To perform this fix you must be comfortable accessing "hidden" files. To access items in your Library, in Finder, hold down the option key and select Library in the Go menu. Go to ~/Library/Mail folder and rename the folder to Mail.old. Go to ~/Library/Preferences, find the file named "com.apple.mail-shared.plist" and rename it to com.apple.mail-shared.plist.old". Go to ~/Library/Containers and find all the folders named "Mail" and move them into a new folder called "Mail.old". Restart your computer and fire up the mail application. Your mail system will be rebuilt and re-indexed. After a while, if everything looks okay you can delete the folders you previously renamed. If everything goes south, you can simply remove the new mail folders in those locations and replace them with the ones you previously renamed. I'm disappointed Apple hasn't taken this issue more seriously. Good luck

Avast security was my problem. It doesn't lay nice with Monterey. Switched to BitDefender. Mailpops up as it shold

Actually I may have spoken too soon.

Since deleting CleanMyMac fully - the problem is not nearly as bad.

My inbox is currently loading in 2 seconds, much improved.

I will see how it's looking and will report back in a day or so.

thanks

Francois1975 wrote:

Since last update with MacOS Monterey, when I open Mail, everything is slow. (In the mail app) I get the color circle every 20-40 second. Spend hours with Apple tech. This is happening on my labtop and desktop. I used Google mail and Microsoft Exchange for work email. We have reinstalled the software and did numerous things with apple tech, and still, not fixed. Its only in mail, everything else on both computers are fast and working great. I have removed all my emails and it's still happening. Mail is extremely slow to response. HELP!

Relaunching your Mail.app while holding the Shift key for a bit of a safeboot—see if this gets you any further.

Did you try simply re-install the macOS on top of your existing macOS...?

This will refresh all baked in applications like your Mail.app. to sort anomalies. This choice will leave your user data untouched.

reinstall macOS Recovery — How to reinstall macOS - Apple Support

You could try this (we had this issue with Mac Mail Client)

--Create & use App Passwords--

1. Go to your Google Account. https://myaccount.google.com/

2. Select Security.

3. Under "Signing in to Google," select App Passwords. You may need to sign in.

4. At the bottom, choose Select app (Mail) and choose the app you using Select device (Mac) and choose the device you're using.

5. Follow the instructions to enter the App Password.

6. Tap Done.

-Mac Mail Client Configuration-

1. From the menu bar in Mail, choose Mail > Add Account.

2. Select your email provider from the list as other mail account, then click Continue.

3. use 16 digit app password instead of google account password press sign in and it would end up with asking IMAP/SMTP settings.

4. set IMAP and SMTP as follows

-Incoming Mail (IMAP) Server: imap.gmail.com

-Outgoing Mail (SMTP) Server: smtp.gmail.com

As explained higher, just delete the following file:

~/Library/Application Support/Mail/Plug-ins/Bundles/Library/Mail/Bundles/Properties.plist

To do that, in finder, go -> go to folder -> paste: "~/Library/Application Support/Mail/Plug-ins/Bundles/Library/Mail/Bundle" and next delete the appropriate file.

MeltingSnowtime, just to clarify, my slow mail issues started on Monterey and got worse with the last Monterey update 12.6.1. That was why I installed Ventura 13.0 (and 13.0.1 thinking Apple may have fixed something). The slow email was worse with both Ventura updates. Creating a new user account seems to have solved the problem for me, so macOS does not seem to be at fault.

Although not fully confirmed, it looks like my security software Malwarebytes may be the problem. Turn off any anti virus, VPN, etc before opening mail.

I just updated to Ventura OS 13 - Mail works now and I hope that's the end of it.

Just delete the following file

~/Library/Application Support/Mail/Plug-ins/Bundles/Library/Mail/Bundles/Properties.plist

To do that, in finder, go -> go to folder -> paste: "~/Library/Application Support/Mail/Plug-ins/Bundles/Library/Mail/Bundle" and next delete the appropriate file.

Should work fine.

Well my case seems to be different from above and rather mysterious: I had an old comcast.net account that I didn't check much and got a email 'advertisement flyer' from Penfed bank which I ignored, but remarkably the single entry in Apple Mail actually represented hundreds of thousands of duplicate emails that took up 22 GB of storage. I deleted the comcast account from apple mail and deleted all the emails, and performance improved. Remarkably about 5 GB of the same duplicate email was buried in my archive (even after deleting the comcast account) and I deleted that later. Performance improved but rebuilt mailboxes anyway. I contacted comcast and they didn't know why this occurred but said it wasn't a problem on their end, and Penfed was useless, so quite unusual.