My accounts in Mail app stopped to sync post update

Noticed I was having this issue too. Found this thread. Decided to just try completely removing my Gmail account, the one that wasn’t syncing with the Mail App after the iOS 18 update.

I went into Settings — Mail App — Mail Accounts (it’s conveniently the very first thing at the top so easy to find) then selected the account that wasn’t syncing (Gmail, in my case) and then selected Delete Account. In the scary red lettering.

I was a little hesitant but went ahead and let it completely remove all the synced items from the account off of my iPhone. After a minute, it was removed so just went and re-added it and BOOM. Works like normal! No more issues.

(For reference, I use an iPhone 13 Pro with iOS 18)

Possible FIX

Hi, Fixed mine by overtyping the IMAP and SMTP Mail Server settings. Some corruption in one of the text boxes I think. Retype the Name : Password : Port, text lines in your Email client. Verify and Save.

I have just had a call with Apple support and the Engineer had me remove old (and not used for a number of years) VPN config on multiple devices after we demonstrated the issue and the issue looks to be resolved. Suspect some Apple Dev's have been lazy with some code in IOS18's mail.app and its causing the issue.

Hotmail will not sync on iPhone Mail app, very frustrating. How difficult is it to get email to work, surely a basic issue before you release a major update like this? Lazy, lazy lazy - not what I expect (or pay for) from Apple - please fix it soon

Oct 2 I just did this and it worked...

Did anyone else receive this (supposed to be actioned before Sept 30) regarding Hotmail/Outlook etc:

The safety and security of your information is top priority for Microsoft. To help keep your account secure, Microsoft will no longer support the use of third-party email and calendar apps which ask you to sign in with only your Microsoft Account username and password. To keep you safe you will need to use a mail or calendar app which supports Microsoft’s modern authentication methods. If you do not act, your third-party email apps will no longer be able to access your Outlook.com, Hotmail or Live.com email address on September 16th.

What do you need to do?

If you are receiving this email, you are currently using an email or calendar app that uses a less secure authentication method to connect to your Outlook.com email account. You will need to upgrade your third-party mail and calendar app to a version which supports modern authentication methods.

Microsoft provides free versions of Outlook for your PC, Mac, iOS, and Android devices which can be easily downloaded and connect to your email account. Using an updated version of an Outlook application will ensure you are connecting in the most secure way.

How can you set up your Gmail, Apple Mail, or other third-party mail application?

Various non-Microsoft applications will have their own steps for connecting to your Outlook.com email account using modern authentication methods. See our help article - Modern Authentication Methods now needed to continue syncing Outlook Email in non-Microsoft email apps. However, you may need to contact the creators of those applications to provide you with instructions. In many cases, simply removing and re-adding your account with the latest version of that application will configure it to use modern authentication methods.

If you can take a look at your mail server settings specifically the IMAP and SMTP. Make a note of the values and delete an overwrite them also check your passwords for both SMTP and IMAP. Make sure they are the same if you can’t see them look at the number of stars or dots. Look at the mail server settings boxes for password and port settings they’re the ones you need to delete and reapply.

Same here. Update iOS 18.0.1 did NOT fix the issue with IMAPS and the Apple Mail App - sad!

On a side note - MacOS 15.0.1 broke my Apple Mail app on my M2 Mac Mini (worked perfectly fine under MacOS 15). It now crashes when trying to open the app...looks like things are getting worse instead of getting better...

if you have mutliple google with their oauth accouns and multiple imap accounts ... how long takes to reconfigure them with "may be luck happens" option ??? apple show their smartness already Month ...

It's October 15th and I'm running the latest iOS 15.0.1. The Mail app is not working properly. Some emails won't load, and others are not updating my sent emails. I've tried deleting and re-adding my accounts following all the correct steps, but nothing works. I didn't realize this was a known issue for many users. The Mail app is very important, and I really hope Apple is taking this seriously and will fix it soon.

Join the club. Mine has been doing that exactly. Until they fix it download the Edison Mail app. It's a free service where you can access all your email services in one place. Works great and it has no issues like we are experiencing with ios18.

Did you already force restart your iPhone?

Force restart iPhone - Apple Support

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.

@coolgrljen

Did you check if the password for the incoming mail server is still listed in the Mail account settings?

Did you try to set up the Mail account again?

@Fai545

Did you deinstall the Beta profile before updating to the official iOS 18 version?

Is this a 3rd party mail account?

Can you see your mail if you use log into your Webmail account?