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No push notification on iOS Mail app
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I've seen other posts here that push on iOS native Mail app works but I haven't been successful. I can send and receive email from my mailbox.org email and alias using the app. However it is only after I open the iOS Mail app does the message show up in the inbox. I have set the account to use "push" in iOS. What else do I need to do to get iOS Mail to receive pushed emails and provide a notification?
The same question 
Update: I cleared everything on my DNS and restarted the process. Seems that fixed whatever the problem was and I'm now getting push notifications on my iPhone.
and it is back to no longer pushing a notification....
Has anyone had success in this? What are your settings?
Yes, notifications from the Apple Mail app on iOS are terrible. I had better luck using the Exchange end-point vs. the IMAP end-point but with the latter, changing the mail retrieval from Push to Fetch also didn't make a difference. I now use Outlook on iOS to get reliable notifications for email; it has its own issues (rendering) but the notifications are very reliable. I must clarify that no other email client on any other platform has had any trouble with this for me - Apple Mail on iOS just appears to be a terrible product for all services except iCloud.
In my case, Mail app was not allowed to show notifications for some reason, so the fix was to go to Settings -> Notifications -> Mail, then Enable "Allow Notifications" and allow all alerts (Lock Screen, Notification Center, Banners).
Also make sure your account is set to Push in Settings -> Passwords & Accounts -> Fetch New Data. Enable "Push" at the top, then set your account to "Push".
One more thing: push notifications for my personal domain didn't work with IMAP, but worked fine with Exchange ActiveSync.
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