Posting here for wider visibility...
All over the internet, apple discussions, etc. Seems that this is affecting thousands of people but apparently not millions...othewise we'd have a fix by now. This started showing up in iOS 18 beta and then continued into 18.0, 18.1, and now 18.2
Symptoms are unable to retrieve emails from IMAP mail server. Some have mentioned Dovecot IMAP server. This author happens to have Dovecot IMAP and yes, once iOS 18.0, 18.x was installed, email sync no longer works.
Thanks for mentioning this.
Users are experiencing this issue on different IMAP servers, like Gmail or iCloud.
I am also affected by this and only use iCloud Mail servers.
The strange thing is: emails cannot be received, or the Mail app hangs for an extended period before finally receiving emails. I can also observe this behavior on macOS 15.2.
I troubleshooted the issue and in my case I found some dependencies on Private Relay.
Normally, PR is not used if the device receives an NXDOMAIN response from the DNS servers for the masking URLs of Private Relay.
Many companies block these URLs to prevent bypassing their infrastructure. However, it now seems that this is not working as expected.
I can see a massive increase in retries to resolve these domains, which are still being blocked by our backend infrastructure.
In the end, many devices run into issues with mail delivery. Bypassing the PR URLs is a workaround, but in most cases, it’s not a suitable solution.
Hi, I install 32bit imap server with cyrus-imapd and access to account is working. After switch to 64bit is broken (other client are still ok). Maybe it will help you.
I have no private relay enabled. iPadOS Mail client continues to work just fine and is running 17.x...my macOS is at Sequoia 15.1.1 and I'm planning to hold off on 15.2 until I hear iOS 18 fixes mail or that 15.2 doesn't break Mail.
So if I deleted my IMAP mail account on the iPhone, quit Mail app, then re-add the IMAP mail account. I get the current set of mail. Thereafter, I don't. I've tested with both Push and Fetch and it doesn't seem to make any difference. It defaults on my account to Push which should be accurate since I have Push Notifications setup on that old macOS Mail server with a valid certificate.
I am of the understanding that Apple no longer supports connections with older SHA1 type encryption. It still supports TLS 1.2 but with dovecot some versions are limited as to their lack of support for SHA 2. Is anyone at Apple able to shed any light on this subject as it makes sysadmins life a misery to not have documentation from them on this.
just to clarify, this widely discussed problem is not related to encryption, certs, nor VPN, although other mail issues may be reported This problem is about broken sync of mailbox in iOS 18 mail with IMAP.
https://discussions.apple.com/thread/255760058?login=true&sortBy=newest_first
Oddly this thread got locked when it started heating up...nothing to do with inactivity.