Mail is Slow and lagging.

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'm having exactly the same problem with Monterey v. 12.5. Problem is intermittent; sometimes leaving Mail app for another app and then returning to Mail solves the problem (for one or two Mail use times) but other times it doesn't. Very frustrating that Apple can't resolve this.

App Passwords can only be used with accounts that have 2-Step Verification turned on.

--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

I have a M1 MacBook Air, an M1 Mac mini and a 14" MacBook Pro M1 Max.

All are always updated to the lasted Mac OS Monterey (currently 12.5.1)

I have three Mail accounts (Apple iCloud, Gmail, Comcast) all configured in Apple Mail app on each Mac.

M1 MacBook Air and M1 Mac Mini have always been just fine in Mail performance.

Mail performance on the 14" MacBook Pro M1 Max is horrible. Blank Mail windows for 5 to 10 seconds until messages listing are displayed. Switching between accounts takes 10 to 20 seconds until the Mail app messages listing is displayed. I have tried rebuilding mailboxes, no change. Restarting the Mac helps, but then degrades and gets worse until next restart.

Again, only the 14" MacBook Pro M1 Max has poor Mail app performance. All Mail settings are exactly the same on all three Macs.

I have been having the same issues, especially since upgrading to Monterrey. The entire system is slower and I am losing time and money to the extent of 2-3 hours every day due to slow, painfully slow Mail. It is getting to the stage where after twenty years I am contemplating a move away from Apple altogether ...

Hi Jimmych1,

Been dealing with this for months. Final solution found Saturday. My Mac was 6+ years old. Saw gradual decline as each new OS was added. Finally slow mail was the killer. Bought new Mac and it is WONDERFUL. Don't know age of your equipment...just say-un...creeping obsolescence !

I have three Macs, in my case, the newest one: 14" MacBook Pro M1 Max is the only one that's really slow ... and only on the Mail app:

I have a M1 MacBook Air, an M1 Mac mini and a 14" MacBook Pro M1 Max.

All are always updated to the lasted Mac OS Monterey (currently 12.5.1)

I have three Mail accounts (Apple iCloud, Gmail, Comcast) all configured in Apple Mail app on each Mac.

M1 MacBook Air and M1 Mac Mini have always been just fine in Mail performance.

Mail performance on the 14" MacBook Pro M1 Max is horrible. Blank Mail windows for 5 to 10 seconds until messages listing are displayed. Switching between accounts takes 10 to 20 seconds until the Mail app messages listing is displayed. I have tried rebuilding mailboxes, no change. Restarting the Mac helps, but then degrades and gets worse until next restart.

Again, only the 14" MacBook Pro M1 Max has poor Mail app performance. All Mail settings are exactly the same on all three Macs.

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.

It gets worse and worse - but whatever you do, don't ask Apple to resolve it! In the interim since I posted, I have spent several days, lost access to my entire account (I had two operating on my computer) and the second smaller account is even slower ... I have temporarily resorted to using Zoho Mail and pray each day that Apple will get this fixed:-))))

I have the same issue. Brand new M1 Ultra. Mail is PAINFULLY slow. Takes a full minute to load my inbox. Takes another minute to load sent mail or any other folder.

I've tried EVERYTHING, from reinstalling the OS to using CleanmyMac to starting in safemode to rebuilding the inbox to removing and re-adding the icloud accounts. Only happening on my desktop. My laptop mail is fine.

Seriously infuriating especially since Apple doesn't care about this pervasive issue. I will no longer use icloud for email, switching to Gmail and will have to use a browser for my email on my brand new $5,000 machine. Unbelievable.

Ditto - and I have put off buying any new Apple equipment until I see a resolution on this - it is such a fundamental tool for my work (online marketing) and like you, I have gone to Apple directly for help, a number of times over a year or so now, and the proposed soloutions are myopic and ineffectual.

The situation has been exacerbated since the introduction of Monterey, I have also tried CleanMyMac etc (no visible effect) - this needs attention and a failure to resolve these software issues means that Apple, despite their great marketing are slowly deteriorating to become a branded box maker and not a branded lifestyle tool.

Like you I am currently running one account on Google Mail and another on Zoho Mail - both are far far better and I guess the only hope now is that Apple will buy Zoho and give us that upgrade as a solution ...

'If I am focused on one email message and waiting for it to "appear" I can quit mail and instantly reopen mail and the message is there in full, graphics, everything. If I then scroll to the next message, it is blank. I repeat the process, close mail, reopen and viola there is the message in full."

Sort of the same here on a 2015 iMac running the latest OS. I can immediately see all the headings, but message fields are blank for a couple of minutes. I go browsing while waiting. If I need to peek at my messages immediately, I take a look at the Mail iOS app on my iPhone. I am due for a new iMac so maybe that will end the problem.

Using an iMac 2015 and running Monterey 12.6 and Apple email the header pops up immediately. Occasionally the body of the email message will come up in a few seconds, however now the body only appears intermittently when it appears at all. Usually it now starts blank and remains blank. Apple is completely unresponsive with a solution. What will work for me (at least for a while ...) is to right mouse click on the subdued forward or reverse arrow in the header's bottom border line. The sought message opens as the body of a blank forward message format almost instantly, however any embedded hyperlinks in the body can only be opened by right mouse clicking on the link, then clicking again on the menu command "Open Link". As I said, this is Apple's problem, not a user error, and Apple doesn't seem to be making any effort to work with us to resolve it or even contact us to explain why Apple isn't going to fix it.

"... I've tried EVERYTHING, from reinstalling the OS to using CleanmyMac to starting in safemode to rebuilding the inbox to removing and re-adding the icloud accounts..."

So I just tried CleanMyMacX (CMMX). I have used it every week for maybe ten years in its general Smart Scan mode, but had not tried its specific tools for Mail Attachments (under Cleanup) and Maintenance (under Speed). Today I used both of those tools, then looked and saw 8 emails in my Mail Inbox on the iPhone. I launched Mail on the iMac and expected to see those emails having the problem of headers with no messages visible for awhile. But instead, all the messages were immediately visible.

While writing this, Mail received 3 more emails, whole messages were also immediately visible.

CMMX is not well-regarded by some on this forum. I don't know why; perhaps it is identified with Mac Cleaner which evidently does have problems. After ten years, and now this apparent success against the Mail problem, I am even more impressed with CMMX.