My accounts in Mail app stopped to sync post update

Same issue. I deleted apple mail app, reinstalled, added account again. No fix. Can send email but no syncing with server.

i then installed 3rd party email app. Works perfectly.

its definitely IMAPS.

account settings > advanced

turn off use SSL, change port to 143.

I found that rebooting my phone seemed to do the trick for a while

Just updated to IOS and IPADos 18.1 and now all my mail accounts work again, it was just all about patience 😊

If you can not receive iCloud mail, go to Settings/Your Name/iCloud/Mail/iCloud Mail, and make sure, that "Use on this iPhone" is enabled.

Set up iCloud Mail on all your devices - Apple Support

Troubleshooting can be found in this article:

If iCloud Mail isn't working - Apple Support

I did not run into any issues using my 3rd party mail accounts or iCloud Mail on my iPhone after the iOS 18 upgrade.

@ingo2711 if you are referring to my comment --

I have deleted the account 20 times. I deleted the Apple Mail app from the phone, reinstalled from the App Store. it didn't help.

my comment about 3rd party email -- is a 3rd email app called Email - Edison Mail (from the App Store) I set up my mail accounts in the app and everything works as it should.

BTW - I never had the iOS 18 beta.

https://apps.apple.com/us/app/email-edison-mail/id922793622

The issue is with the Apple mail app.

Same issue here, both iPhone and iPad updated to 18, inbound mail using imap from our own servers.

I did some investigation, and I find that the imap server drops the connection due to inactivity.

i guess something is seriously broken in a part where the start retrieval of message is skipped in the iOS 18 mail app.

M.

The biggest issue seems to be with third-party servers using self-signed SSL certificates. Apple is making it harder to establish a handshake with self-signed certificates, but this only affects email. The calendar is working fine so far.

We're using an OS X server with a self-signed certificate, and I can see the error in the server log.

TLS handshaking: SSL_accept() failed: error:14094416:SSL routines:SSL3_READ_BYTES:sslv3 alert certificate unknown: SSL alert number 46

I had the same issue with the mail.app and using register.com. All worked fine before I changed to IOS18. After I did, I was unable to send emails and received an INVALID ADDRESS response. I stopped in at the Apple Store and they couldn't help me neither did two calls to Apple, and one to REGISTER.COM. However, this morning, I spoke with Applecare support named Michelle and she suggested I add my user name and password to the outgoing mail server where it says optional. I did and VOILA! I'm back in business. May not work for everyone, but it did for me.

I tried to do a tcpdump between IOS 18 device and my mail server.

So, Layer TCP (SYN, ACK, etc.), TLS 1.2 (Cert, Cipher, etc.) and IMAP Proto all work. The mail application logs in IMAP and immediately logs out with EOF and back to the beginning. Meanwhile, the spinner runs in the app and the user no longer receives any messages.

So, the Mail APP looks for the contents of the inbox, but the device has already cut off communication with the mail server.

agentogden wrote:

its definitely IMAPS.

account settings > advanced

turn off use SSL, change port to 143.

Sadly that option won’t work for many as tons of servers are set to refuse non secure connections. That’s the issue I have. One server will just say “connection refused”, the other mail server will actually block a second connection attempt that’s not ssl or TLS.

so, I’m glad to read that you can make it work for you but consider it lucky that your server will allow you to go with insecure connections.

Hi,

I had a similar issue with my email disappearing from multiple accounts, and after troubleshooting, I discovered that the problem was related to my self-hosted IMAP mail service on Synology. After updating the SSL certificate, the issue was resolved, and all my emails reappeared. If you're using a self-hosted solution, I recommend checking your SSL certificate as well.

Hope this helps!

The Comcast (Xfinity) level 3 technician, a MacBook user, said that the problem is a synchronization issue. He said that there are YouTube videos explaining how to fix the problem by repeatedly setting up one’s client email account until you get lucky and the two systems synch. This can take many attempts. Until Apple releases the fix, using your ISP online email site is the only thing that can be done.

On October 20th, my mom spent over an hour on the phone with Apple, trying to resolve an issue with her iPhone 16 Pro Max: Gmail wasn't working in the iOS 18 Mail App. Unfortunately, they weren't able to provide a solution. Everything points to a bug in the Mail App. As a temporary fix, she downloaded the official Gmail App to manage her Google emails while continuing to use the iOS Mail App for her non-Google emails.

TLDR; this issue doesn’t seem to be an apple issue - its a Google issue 🥴 And there doesn’t seem to be a good way to contact Google.. (but I am persistent and I’m not going to give up!!)

This morning (10/26/24) I had an hour long phone conversation with a wonderful Apple senior support advisor regarding this issue.

Background: I have 3 accounts on my mail app; my iCloud account (we’ll call this “account A”) and 2 gmail accounts (“account B” and “account C”. After updating my iPad to iOS 18, one of my gmail accounts, “account C” was not syncing properly on the ipad. The other gmail account, “account B” and my iCloud account, “account A” were acting as they should.

If I read emails or deleted emails on my iPhone in “Account C”, it was not reflecting that on my iPad. My unread mail count on my ipad for “account C” quickly grew to over 2000. I tried deleting “account C”, restarting my ipad, and reinstalling “account C”… and no change.

During my call with senior support this morning, we checked various settings on apple mail, gmail app, and gmail web browser. We did this for “account C” and also compared them against the “account B” which was working fine. There were NO differences in the settings.

All signs are pointing to an issue on googles side. The apple senior support advisor and myself tried to figure out a way to contact google/gmail support, and there doesn’t seem to be one. There is a gmail community (similar to this) where you can post issues .. so hopefully if enough people post about it, google/gmail will fix the issue! Here’s the link to the Gmail Help Community

-kp