Mail not working on iPhone after iOS 18 Update

None of this advice is relevant to this issue. As I replied to someone else above, the very same mail account can send mail using iOS mail app - which means the phone can authenticate the account AND TLS works. The issue is the the iOS and iPadOS mail app fails to get new mail from imap servers. This is a bug. . It’s very disappointing to see Apple make a mistake in such a primary function.

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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...

I can't believe it, but simply turning on airplane mode and turning it off again worked for me also!! (This is after trying a reboot, which did not work.) I was missing all my work emails, work calendar and work contacts. All back now, can't thank you enough!!

For what it’s worth, after 3 days of the mail app not updating, I shutdown my phone, waited 10 minutes, restarted the phone and the mail app started working. It now appears to still be working a couple of hours later.

Was having the same issue. I deleted my Hotmail, tried re-adding multiple times. Restarted the phone several times and still didn’t work.

Finally got it working again by adding the account through “outlook.com” tab…. No longer “other” as I always did before. Can still name it “Hotmail” as the description.

Hope this helps others!

Sadly it doesn't! I'm hoping when 18.1 finally comes out it will address this.

I personally tried everything so far. Deleted app, deleted accounts, readded them, erased iPhone, restored from backup, restore as new, forward slash, "INBOX", changing auth methods, changing push/fetch etc.

Nothing worked. And behaviour is the same as mostly everyone else. IMAP fails to fetch new emails despite SMTP working just fine. All my servers are my own work servers running on OSX 10.13.6 on Server 5.6.1. TLS is 1.2

MacOS is unaffected only iOS18 and 18.0.1 and also ofc iPad OS. iOS 17.7 still works just fine but Apple stopped signing those so hurrray for no ability to rollback either.

Initially, I replaced the "grayed" out / with one I typed over it. That made it bold/normal in color. But, it did not solve my issue. So I went back, and typed an additional / next to the / I had previously replaced the grayed out / with. So at Settings>Apps>Mail>Mail Accounts>"My Account">Account Settings>Advanced> Under "INCOMING SETTINGS" I had: IMAP Path Prefix // with the second / to the right being the one I added. I then clicked in between the two // and backspaced out the one to the left or the one that I replaced the original gray one with. After that I did a hard reboot of my phone and the mail worked.

Same with my email. No longer can download mails on cellular network but can on wifi. It turned out that after updating to ios 18 several apps that were switced on cellular were off after the upgrade. So check to see if cellular switch is on

Out of curiosity, has any spoken to an Apple tech? To my knowledge, Apple has not officially acknowledged a problem ....

I suspect people may be having different symptoms due to their phone configuration and obviously some never had the problem. I have posted this before, but below is how I resolved the issue on my phone:

 - Go to your phone …

 - Go to Settings … scroll all the way down to Apps …

 - Go specifically to: Settings>Apps>Mail>Mail Accounts>Select your mail account>Account Settings>Advanced

 - In the group “INCOMING SETTINGS,” the second line should read: "IMAP Path Prefix /“

 - You may notice the forward slash “/“ is grayed out and not the same contrast as the three words prior.

 - Type a forward backslash “/“ next to the grayed out /

 - Now delete the grayed out forward backslash “/“ - Just tap to the left of the new backslash you typed and backspace to delete the grayed out backslash.

 - Finally, perform a hard reboot of your phone in the following order: 1. Press and release the left outside volume up button. 2. Press and release the left outside volume down button. 3. Press and HOLD the right outside power button UNTIL the phone shuts down, restarts AND you see the Apple. DO NOT slide the power down “slide button” during the shutdown. Keep your finger on the power button UNTIL you see the Apple upon restart.

I received the answer from my email provider, that the IMAP issue is caused by a bug in iOS 18 and iPadOS 18.

They suggested to report my problem to Apple and shared the following article, as it is a known issue:

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Not sure if this has been mentioned, switch to cellular by toggling off WiFi. Lots of updating issues with WiFi is being used, especially with the mail app. I'm on 18.2 and have been having to do this since 18.

I tried the solutions suggested here and none of them worked. So I downloaded the Gmail app, signed in with my email addresses there (I have more than one) and hey presto - now I have emails on my Gmail app and the Mail app started working too. No idea why this worked but it did. I’ll delete the Gmail app if Mail keeps working. It’s a pfaff but it worked.

This fixed the issue for me:

1. Go to: Settings > Apps > Mail.
2. Select: Mail Accounts.
3. Choose the account with the issue.
4. Toggle off the Mail button for the account.

• • If the password isn’t the issue, toggling it off and back on may resolve the problem.

1. When prompted, enter the new password (if applicable).
2. Toggle the Mail button back on to ensure the mailbox reappears in the app.

This is what worked when i got the message "cannot get mail":

Steps to Update Your Email Password:

1. Go to: Settings > Apps > Mail.
2. Select: Mail Accounts.
3. Choose the account that requires a password update.
4. Toggle off the Mail button.
5. When prompted, enter the new password.
6. Toggle the Mail button back on (if needed) to ensure the mailbox reappears in the app.

Recently upgraded one phone from 17 to 18.1.1 and now have this issue. Reading the comments on this thread it is clearly an OS issue. As many have stated mail can be sent so the communication is not broken with the server. As more evidence a device running 17 has no issues with communicating with the exact same email configurations. Finally, the account was deleted and reentered. The first connection has no issues pulling the emails or allowing me to "TRUST" the certificate when presented. However the first fetch call breaks and returns the error [... "bad certificate format" -9808]

I hope this is getting attention by developers and some solution is on the way. Access to my email has become one of the prime functions of my phone and seeing to delete and recreate every time I want to "pull" email is not only inconvenient but unacceptable on a release that already has one an update, a patch applied, and reports going back weeks of the issue.