Mail not working on iPhone after iOS 18 Update

Indeed. See my earlier post and you'll see I spent hours on a call with Apple Support and they had me install MS Outlook to confirm it wasn't some network issue, despite my sharing the email server logs that showed that the Mail app was not responding after making a connection. Super weird.

So, know we know that the following email clients work with iOS18 (and presumably iPadOS 18, because they are close cousins and both are exhibiting this problem):

• Microsoft Outlook
• Spark Mail
• Canary Mail

Logged in to confirm the problem on iOS18 with an older mailserver.

Mail connects and reports that it has just updated but no messages visible.

Work around was to turn off SSL in Advanced Settings. Portnumber will automatically switch from 993 to 143.

If this disallowing a 'not so secure' SSL version is on purpose then it has the opposite effect: we'll just switch off SSL. Great idea!! (sarcasm intended)

Someone a week or so noticed the forward slash "/" was "grayed out" at Setting>s>Apps>Mail>Mail Accounts>YOUR Mail Account>Account Settings>Advanced>IMAP Path Prefix / (the "/" is a light gray)

So the person suggested typing in a new forward slash over the gray forward slash, and then "backing out" with a "Done" to save the change. I did this, but my problem continued. So here is what I did instead:

• I again went to ... >Mail> ... "IMAP Path Prefix /" This time I typed a "/" next to the grayed out / and then using my backspace, I deleted the grayed out /, leaving the new one I typed.
• I then hit "Back" and then "Done" and got exited Settings.
• Lastly, I did a hard boot reset of my phone: 1. Press and release side button volume up. 2. Press and release side button volume down. 3. Hold right side power button UNTIL phone shuts down (DON'T swipe the shutdown switch) AND the phone restarts WITH the Apple. THEN, release power button, but only after seeing the Apple upon restart.

After doing this, my mail is working properly. Don't know if it is coincidence or if Apple remotely fixed the problem. I am inclined to think Apple has not resolved the problem yet, because I still see postings on this sight.

Here is how I eliminated the iOS mail problem. Not sure if it was coincidence or a remote fix by Apple, but I still see people posting issues on this forum, so I presume the problem persists. Here is what I did:

 - 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.

After doing all this, the mail on my phone is now working properly.

Same, went to genius bar, they deleted the mail account, re-added. Working again. They claimed a sync issue with Microsoft and or Google.

Try what I did. Deleting your mail account and then restarting your phone. It seems to work for most people. Restarting was the key.

You really DO need to contact your relevant external (external to Apple) email service provider about the problem; for me it was a behind-the-scenes fix that Comcast did - at least on my Comcast email accounts - that permanently resolved it. If your provider’s customer service or tech support rep says they have no idea what you’re talking about tell them to escalate it in order to work it out with Apple. I made only 1 call to Comcast about it and was told they were aware of the problem and expected to have it resolved within 24 hours (which they did, although as I recall I found that I did have to delete and reinstall my Comcast email accounts within iOS mail to complete the fix at my end once Comcast completed their work on it).

Found that I could not send emails after updating to iOS 18 on my iPhone. Came across a suggestion that I should renter my “password” in “Settings - email account”. Never thought for one moment it would solve my problem; but it did.

So this happened to me after the iPhone upgraded to 18.3.1. Basically all my other devices sent and received emails through OS X mail function with the exception of the iPhone. I spoke to Apple services on multiple occasions and nothing worked except for one process. This was to disconnect the phone from iCloud and then restart it. Once I had done this mail worked! For information if anyone is similarly stuck a workaround to use mail other than the Apple OS X app is to download an alternative mail application and use that with the mail email address. I did that for a week while I was sorting out the OSX mail app. Hope this is some help.

FYI after trying multiple fixes attempts which failed I used an alternative non osx mail app, of which there a number and used it to just see emails from the me.com mail account. Then I tried again to disconnect the phone from icloud completely and reconnected and that worked…it’s been fine since. By then I had escalated this as an apple tech complaint, so it is just possible that separate to the above they fixed it behind the scenes, but I never received any follow-up or notification that it was working now again. Hope this comment helps.

Yup, that did it. I tried before, but didn't restart. Restarted and voila, it worked. I'm using 18.0.1. Thanks.

I found that I had a non printing character on one of the folders on my IMAP server. Renaming this folder to remove the non printing characters fixed all the mail app problems for me.

Delete the email account not the app. Then reinstall the email account.

It worked for me.

I too experienced issues but only on my iPhone. I contacted support, deleted the account that wasn’t working. Reloaded it and it worked

It’s iOS fault, this issue has occurred to many users after update to iOS 18. Unfortunately Apple doesn’t display the version of supported TLS or any information about the error. In my case is TLS 1.2 and I have the same issue.