I don't know what happened to my iPhone sync of my Hotmail account within Mail. It was working great and now it has stopped working about 2 months ago. Do I need to delete my Hotmail account and re-install it or is there a way to get the Mail sync to work again with the Hotmail account?
iPhone 6, iOS 9.3.2
Get help with Mail on your iPhone, iPad, and iPod touch - Apple Support
If you have already attempted everything else in this article, then yes it is recommended to remove the mail account and add it back again to troubleshoot this issue. Depending on the security settings of your email provider, Hotmail, you may have to setup an app password to be specifically used with your iPhone Mail app. That much is covered in the following article from Microsoft, owner of Hotmail.
http://windows.microsoft.com/en-us/windows/app-passwords-two-step-verification
Try resetting your Mail Account. First close your Mail App completely from the app switcher window by double clicking the Home button and swiping up the Mail preview pane up until it disappears from the screen. Then go to Settings > Mail, Contacts, Calendars > locate your email provider and click on the account. On the next page Delete Account. Then do a forced restart. Hold down the Home and Wake/Sleep buttons at the same time for about 15-20 seconds until the Apple logo appears. Then go back to Settings > Mail… and add the account again.
I have this issue too, it's been about 2 months now. I've deleted my email account three times now and the same problem eventually occurs. Super frustrating. Any idea why this is happening or what more to do?
Hotmail Sync Issues
