Mail not working on iPhone after iOS 18 Update

You are very lucky. I just did the update and the problem is still there. Were (Are) there multiple bugs?

I added / a few days ago but today I’m getting my “flashing” emails for “All emails” and I’m definitely not loading 18.1.

Fix this bug Apple !!!!

Hi 
Does anyone still have the problem 
with IMAP accounts in the MAIL App, 
I can't seem to solve it?

YES!! I still have that issue.

hello195 wrote:

Hi

Does anyone still have the problem

with IMAP accounts in the MAIL App,

I can't seem to solve it?

Yes, the problem remains.

it is an iOS/ipados 18.1 bug in the mail app.

Hundreds of us>……

Same here! At least in my case I still have one mobile device I did not update to IOS 18. But, I had plans to upgrade that device this year! Going to have to wait until this bug is squashed.

Me two. None of the fixes suggested on this entire thread have worked.

Still have a problem with self signed certificate after upgrading to 18.1

Using sendmail 8.17.1 and dovecot v2.3.20

The mail client error is "Posix 50" and/or "invalid certificate format -9 808"

Delete / added the account multiple times.

Other mail clients works fine, Bluebird (IOS),stock mail MAC Airbook (Sonoma 14.6.1)

Bluebird (Fedora FC40)

here is the essential from the dovecot log (ssl debug)

Nov 07 07:18:17 imap-login: Debug: SSL: where=0x10, ret=1: before SSL initialization

Nov 07 07:18:17 imap-login: Debug: SSL: where=0x2001, ret=1: before SSL initialization

Nov 07 07:18:17 imap-login: Debug: SSL: where=0x2002, ret=-1: before SSL initialization

Nov 07 07:18:17 imap-login: Debug: SSL: where=0x2001, ret=1: before SSL initialization

Nov 07 07:18:17 imap-login: Debug: SSL: where=0x2001, ret=1: SSLv3/TLS read client hello

Nov 07 07:18:17 imap-login: Debug: SSL: where=0x2001, ret=1: SSLv3/TLS write server hello

Nov 07 07:18:17 imap-login: Debug: SSL: where=0x2001, ret=1: SSLv3/TLS write change cipher spec

Nov 07 07:18:17 imap-login: Debug: SSL: where=0x2001, ret=1: TLSv1.3 write encrypted extensions

Nov 07 07:18:17 imap-login: Debug: SSL: where=0x2001, ret=1: SSLv3/TLS write certificate

Nov 07 07:18:17 imap-login: Debug: SSL: where=0x2001, ret=1: TLSv1.3 write server certificate verify

Nov 07 07:18:17 imap-login: Debug: SSL: where=0x2001, ret=1: SSLv3/TLS write finished

Nov 07 07:18:17 imap-login: Debug: SSL: where=0x2001, ret=1: TLSv1.3 early data

Nov 07 07:18:17 imap-login: Debug: SSL: where=0x2002, ret=-1: TLSv1.3 early data

Nov 07 07:18:17 imap-login: Debug: SSL: where=0x2002, ret=-1: TLSv1.3 early data

Nov 07 07:18:17 imap-login: Debug: SSL: where=0x2002, ret=-1: TLSv1.3 early data

Nov 07 07:18:17 imap-login: Debug: SSL: where=0x2002, ret=-1: TLSv1.3 early data

Nov 07 07:18:17 imap-login: Debug: SSL alert: where=0x4004, ret=558: fatal certificate unknown

Nov 07 07:18:17 imap-login: Debug: SSL: where=0x2002, ret=-1: error

Nov 07 07:18:17 imap-login: Debug: SSL error: SSL_accept() failed: error:0A000416:SSL routines::sslv3 alert certificate unknown: SSL

alert number 46

Thanks for heads up! That'll make fine addition to my bug report in Feedback app.

polkamatic wrote:

True, but why is the macOS mail app working fine?

I’d think that a mail server not minimally offering TLSv1.2 and forward security would be a more interesting question to investigate and potentially address, but add a scan of the client connection offers here too, and you’ll know whether there are differences in that.

Wouldn’t be the first time (as mentioned by one of the folks in this thread) Zimbra (example) or some other mail server had issues, too. Check for updates there.

Mail servers are ongoing maintenance headaches generally, and not keeping them current just makes for a bigger mess.

And for completeness, this may be a bug in the iPhone mail client, too.

I managed to fix mine. Mail with virginmedia stopped working after i upgraded to 17.7, but worked on my other Ios devices (on 17.6.1 or below). Mail worked on outlook and other IMAP devices. Tried everything, resetting passwords, deleting accounts etc. Finally wondered if the VPN (from Norton) was interfering with TLS or account verification and hey presto account set up worked fine. Hope this helps...

That appears to be central to this issue - previously iOS mail would notice when this email server’s certain rotated and its ask me to trust. 18 appears to be not asking but macOS is.

it makes me wonder what will happen to you when your server’s certificate renews - will you need to delete the account again and do it all over?

KiltedTim wrote:

polkamatic wrote:

True, but why is the macOS mail app working fine?

Because macOS and iOS are NOT the same thing.

Exactly. Bug regressions like this recurring imap fetch failure get fixed in macOS releases.

Same problem here. Mail does not download emails even though the credentials are correct and are accepted by the system. It is a professional Imap account. Problem only on ipad and iphone. On MacOs 15.0 it works perfectly. I tried any solution but it does not work. The same account with the same credentials on the same device works perfectly on Outlook...What a shame.