Mail not working on iPhone after iOS 18 Update

Try using webmail to check your imap server settings.

In webmail account settings it should tell you things about the server setup. These need to match your iOS Mail settings.

Also your email service provider should be ensuring that with each iOS release their imap servers are tested & compliant. With the billions of iPhones out there being tested & compliant to the most used mobile email client is a must do.

Clearly in OS 18 Apple has decided to pursue development of a MAJOR overhaul of the OS but partial implementation has so far resulted in multiple problems that apparently will require a series of MANY incremental updates AND the full cooperation of external product and service providers before full, stable functionality is achievedֶֶ. From my experience the best results at least regarding Mail problems were achieved by contacting (by telephone) both Apple AND my external IMAP mail service provider to ensure that both were aware of my observed problems and that they were in need of making whatever changes necessary in BOTH of their “back ends” to get the problem resolved ASAP… when I did so I was assured by my external email service provider that THEY were already aware of the problem and that they expected to have it fixed at THEIR end within a week or so (which did in fact turn out to be true!) while the APPLE “support” rep. that I spoke with initially professed to be unaware of the issue until I persisted by insisting that I knew for a FACT that a multitude were reporting the very same issues online - eventually he finally took the time to actually check relevant company records and discovered that the issues WERE in fact well documented prior to my call and stated that he had no idea when any “fix” might become available. My external IMAP email provider was WAY more knowledgeable about the matter, anticipated resolution and provided an expected time to resolution than Apple “support” was.

Apple consumer tech support is DEFINITELY not at the level that it once was, apparently now relying more heavily on subcontractors who simply roll us through standardized “troubleshooting” steps that sometimes require us to waste our time with them on the phone until EITHER they conclude that they have no idea what the problem is and so report it to Apple OR they finally - after spending an hour or more with us on the phone - take the time to actually look through company documentation when pressed to do so and then discover that it was indeed a problem already known to Apple but that they have no clue as to when or how long it is expected to take for resolution to be achieved.

This is the kind of thing that happens when a company becomes so big that it produces too many different types of product lines within which it produces too many models with too much hardware (and thus software) variation among them, resulting in higher costs and consumer support staff becoming less able to be truly helpful, ultimately resulting in consumer satisfation decreasing over time. Most automobile manufacturers - especially Japanese - learned the relevant lessons a LONG time ago; “tech” companies not so much. I do not expect Apple to improve in these regards to any significant degree until its revenue and profits suffer to a meaningful degree - something that does not yet seem to have occured. One thing I DO know is that complaining about such issues HERE does NOT result in improvement, as THIS “board” was actually created to take the “load” off of corporate customer tech support by encouraging us consumers to help each other out instead of contacting Apple support. Solution: Be prepared to spend the time and energy necessary to CONTACT APPLE customer support (and customer support of relevant external material product and service providers) AS OFTEN AS YOU CAN. That, unfortunately, is the reality of the situation. And if you think OTHER companies of the likes of Apple are much better, I would say you would be mistaken as they ALL “think” alike in these regards.

I found a fix hope this helps.

Must do all fields

imap:*****.com

username: same as email name*******.com

password:******

SMTP all fields must be set up!

SMTP: SMTP***.com

Primary Server ON... Click on advance server

Host Name: smtp***.com

Username: same as email address

password: Fill in password

SSL.. If it applies

Authentication : Password

Server Port: Make sure it is the proper port. Not what IOS mail app set...

This should work.

Please respond and let me know if this helps...

Same problem here.

Must turn OFF SSL on email server to work with iOS 18.

Very inconvenient, worked without issue with iOS 17.

Please Apple fix this.

Try changing authentication to password instead of NTLM 

Worked for me .

jacques

My email hosting company supplied another server name and now working.

Did you try the solution that helped many people on here? Delete all Mail settings, RESTART, then open Mail and redo all settings. The / never worked for me.

If you are running a VPN turn it off

Yes, this is what I have done, submit a ticket at Product Feedback - Apple .

Stomped wrote:

Given the scale of mail usage, there seems to be something wonky about some specific IMAP servers. IMAP is rather less standard than we might prefer, too.

Same problem. After upgrade to iOS 18, both iPad and iPhone cannot download e-mails from one of my business e-mail accounts. When I delete the account and re-add it, everything seems fine. In the last step of adding it, all input is acknowledged with a green check bar. Yet, the download of mail messages is not possible. Sending is no problem. Sometimes I am asked for a password; entering it makes no difference. I am hundred percent sure, that the password is correct. All other mail accounts (including other imap accounts) work just fine.

It is a business account that requires a domain name as part of the user name. Is it possible that this is the problem?

Using an email address as an account name is common.

By the way, with my Macs on Sequoia all e-mail accounts work like a charm as well.

As has been stated, macOS mail client and macOS itself are not identical to iOS mail and iOS.

A fix is urgently needed. Otherwise, both iPhone and iPad are pretty much useless for me.

Apple is undoubtedly aware that they will need to look at the issues being reported.

Thanks.

Though this is looking like an IMAP issue of some sort, also remove any add-on security apps, remove any VPN client apps, and test again. Also check for and remove any “odd” characters in mail folder names using the webmail interface, per another report around here.

Deploying brand-new versions into production without having tested and without having a fallback is unwise, if you absolutely need your gear to work. Major new Apple versions unfortunately aren’t always absolutely stable at first release, which is why various users will wait for problem reports from other users, and some will wait for the x.0.1, x.0.2, x.1 version. Apple made available iOS 17.7 newly available too, and devices can select either that version or can select 18.0, for instance.

Update a spare (older) device to the new version, and test it, for instance.

Apple has previously announced that work on iOS 18.1, iPadOS 18.1, and macOS 15.1 are all underway, but has not provided a release schedule AFAIK, so updates are coming.

Same here. Can send, and message DOES reach recipient, but all IMAP folders stay empty (except for that one message going into the "Sent" folder). Btw, that Sent folder seems NOT to be synchronized with the IMAP server, and is eventually lost (the Sent folder disappears after refreshing folder list). So there must be a bug, probably in the Mail App, probably IMAP only (as SMPTS worked fine). Very frustrating, for me and so many others, and unbelievable that it has not been fixed yet.

Apple Support has informed me that they are aware of the problems with the iOS Mail apps under OS 18. The problems are NOT confined to just external IMAP email accounts but affect Apple email accounts (eg _____@icloud.com) as well. Deleting the Mail app and reinstalling is NOT expected to fix the problems, and doing that is at this point in time NOT recommended by Apple as a possible fix. The problems seem to also extend to issues with mail accounts not being able to properly sync between devices as well. Deleting individual email accounts and re-entering them etc. may OR MAY NOT result in a “permanent” or even temporary fix. So it looks like we’ll have to wait until Apple sorts it all out and issues one or more updates. FYI it looks like mail is working reasonably well on my iPad running iPad OS 18 but mail on my iPhone running iPhone OS 18 is a bit of a disaster. D*mn, I KNEW I should’ve waited at least until 18.1 came out lol!

An update from Apple AND COMCAST XFINITY - Both companies’ tech support reps have told me that MULTIPLE companies (including but not limited to Apple and Comcast) have seen fit to update/upgrade their email security measures all at the same time - NOW - and that has created the problems that people are seeing at this time, with server connections working one minute but not the next, etc. So it is not just Apple’s “fault” per se. Upper level tech support at Comcast told me issues at their end will hopefully be resolved by sometime this evening (at least for MY accounts lol). My recommendation is that everyone experiencing these issues contact not just Apple for assistance but also their iMAP email service providers as well.

For anyone still not getting emails since the iOS18 update, if you’re on Hotmail. Delete it and re add an account. Select the Outlook.com option. It used to be under “other” option which no longer works.

I run a IMAP server with cyrus imapd for a small number of people. Two upgraded to iOS 18 and both do not see new mail arriving in their accounts. They still see the messages from before the upgrade to iOS 18. There are no errors shown on the client and there are no errors in the server logs. In the server logs I can see that the iOS 18 clients authenticate successfully to the IMAP server and that they are accessing their IMAP INBOX Send Items and Trash mailboxes (i.e. asking for a list of the messages that are in these mailboxs). When they send a mail, the send mail is stored in the send items correctly. However other IMAP operations like flagging or moving existing messages result in weird behaviour like making those messages disappear on the client.

This does not look like an authentication or TLS issue at all, something is going wrong in the interaction between iOS 18 mail client and the IMAP server. Nothing changed on the imap server, so Apple changed something that made this happen. This is very a frustrating issues for users, some of them use the iPhone/iPad as their primary means of interacting with their email.