Mail not working on iPhone after iOS 18 Update

I’m also having trouble with emails since the “upgrade”. I tried several remedies I read about on various support pages without success. Like you said, I wish I had waited to upgrade but Apple did the upgrade when I tried to update 17. Very disappointing.

This did not work for me. Neither did removing my account and re-installing it. I can receive email but many messages are dreadfully slow to load. I wish I had waited to “upgrade”. It wasn’t like this with 17.

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.

This is why I dread and hate updates! All you do is break things that were working just fine. I’ve now spent hours, to no avail, to get my Gmail to populate in the mail app, I’ve tried all the suggestions including uninstall reinstall check pop and IMAP server settings to get my mail and it won’t work. This is infuriating! Apple for how ridiculously expensive your products are this basic function shouldn’t be such an issue! Get it together! I’m beyond furious!

After the ISO 18 update on my IPad not only did my emails fail to upload or send on the iPad but I lost all mail stored on my PC which I use in tandem to print up various documents from time to time. Why would this happen.

Will we ever get a fix for this problem as you can’t seem to contact anyone at Apple who take your money🙂

Thanks! That seems to have worked.

One clarification: as you correctly stated, the dimmed / character does need to be replaced, but if the device display is in Day mode the replaced character will appear black.

I tried the "/" fix but this didn't work for me.

I noted some folks tried different client apps other than Mail.

Gmail got the same error but MS Outlook worked fine so I am using that without any problems.

iPhone on 18.1.1

All recommendations in this thread didn't work for me. However, surprisingly, when I reduced the number of emails in my Inbox, it works as expected. I'm not sure what is the maximum number of emails in Inbox but it worked when the number is 1,300.

@sjcorpst - I have that issue from time to time also! Then, later that day or the next day the body of the messages are there! But, I cannot respond to a message or create a new message and send it from that email account.

I can’t add any more email address to my iPhone it’s gone, there is icon to email accounts. WTF is wrong with Apple? This is unexpected and it’s insane as I have 3 addresses and now I can’t add them and have you use my laptop to access my other accounts. Fix this Apple..asap. How could this get by everyone on the last update? Where is the mail icon under general in setting????!

Suddenly, Outlook for Mac is working like a champ. I haven't done anything new, only the same things everybody else has done. I'm still not having consistent luck on my iPhone or iPad using both Apple Mail and Outlook.

I'm wondering if this has to do with the age/version of the device. I have an iPhone XS and my wife has an 11Pro and we have no problem with the Apple Mail app since iOS 18.1. Maybe it is just the newer devices that are having this issue? I'm also not having a problem with my 3 or 4 year old iPad Air.

Note: I just updated to 18.2 and Apple has added some 'features' to the Mail app, none of which I want or need, but others may like them. I turned them all off.

1) Delete the account

2) shut down the phone

3) start phone

4) add account (again)

send and receive should now flow.

Took five times but eventually it worked let’s see if it lasts usually when Apple ignores multiple requests for a problem they feel like they’ve solved it already but still it’s hard to find concrete results. What I listed above worked totally fine and I literally updated the patch this morning, hoping it would fix things, but it didn’t so I did the above steps one more time and had success.

Try to reduce the number of mails in your mailbox. For me, only two mail folders including Inbox and Sent Messages kept failing to be synchronized with my IMAP server. After moving mails in my Inbox to the other folders on macOS mail client, it began to work properly. Sent Messages which has 11,258 emails is still suffering synchronization problem. On the other hand, a mail box which has 4,950 mails is synchronized without problem. I think it' worth trying.

I have an iPhone 16 Pro and iOS 18 (18.1.1 to be exact) and was having the problem of my Mail not syncing between devices. This suggested fix took care of that issue. I’m not on a business server; I’m a standard client on Comcast.