ios 18 mail stuck in "checking for mail"

I had the same issue. Resolved by whitelisting "mask.icloud.com" and "mask-h2.icloud.com" on my DNS.

Check that those two urls are not blocked by your network, VPN provider, or ad blocks apps.

Same for me. Apple’s QA isn’t what it once was.

iPhone 13 Pro Max has the same issue after iOS 18.1 update despite deleting and reinstalling the email provider and restarting the phone multiple times.

any fixes??

Following an update to ios 18 this same thing has happened here. IMAP account stuck on "Checking for Mail" with an eventual error message. I deleted the account and the Mail app. Re-installed the IMAP account. Same thing occurred and messages not being received in a timely manner. Not sure what else to do.

I have the same on iPhone 16 Pro running iOS 18.1.1 using IMAP. No new emails come in and the status bar says “checking for mail”. Removing and adding the mail account doesn’t help.

One thing that does work for me is completely closing the Mail app using app switcher view. After restart all emails get synced, but after a while the Mail app gets stuck in “checking for email” again.

This did the trick. I use Pihole for ad blocking on my home network, adding these to the whitelist worked instantly.

Why does it use a "mask" domain though? It seems to be related to Mail's privacy protection feature. After disabling the "Hide IP address" option the query dor mask.icloud.com disappeared from my query log.

I don't know why it was enabled in the first place since I never enabled it and it was working fine prior to iOS 18.1 update.

DeadCanard wrote:

Since the first iOS 18, my IMAP account works just fine after setting up then a few hours later or sometimes a day later, it just gets stuck in "Checking for mail" when trying to update my inbox. Though I can access other folders just fine. And the unread count in inbox seems to be correct.

Uninstalling/Reinstalling the mail app fixes the problem for a while but it usually comes back. Though it seems that if it doesn't get stuck for a couple of days, the problem does not come back until the next OS update.

The IMAP account works just fine the Mail.app on macOS 14 and 15 , iOS 17. I really never had had an issue before iOS 18. I used the feedback form during the beta but it has not been addressed.

Any suggestions welcome

[Edited by Moderator]

Report the issue your IMAP provider or look at their help site.

Same issue. No such problem with a MacPro that's much older than my phone.

I sent a test email to my iCloud address from my iPhone, using my iCloud address. That came through. For my email account, my service provider says that the IMAP for incoming is correct. The problem is with Apple, and it's happened before. Google it: complaints about the same issue with updates to iOS 16. I can't get assistance anywhere

iam_ttl wrote:

I had the same issue. Resolved by whitelisting "mask.icloud.com" and "mask-h2.icloud.com" on my DNS.

Check that those two urls are not blocked by your network, VPN provider, or ad blocks apps.

I can confirm that allow-listing these two hostnames fixed the issue for me!

I’ve just deleted and added my accounts again and it does the same thing

Somehow it works for me now, but it’s intermittent. So I don’t think I’m out of the woods, as I haven’t done anything different to fix it

Same thing for me

Same issue on 18.2.1 with iPhone 16 and 14 pro max!

I was on the phone with Apple support and the problem was fixed. I had to delete the Apple email app on the iPad, reinstall the app, and then add the email account. Because I was using the POP protocol, all of email in all of the folders on my iPad was lost. Fortunately, I had my full inbox on another PC, but I lost the emails in the drafts and sent folders on the iPad.