For Microsoft Exchange 2013 and iPhone/iPad from iOS version 11 and up
This article explains how to set up a Microsoft Exchange 2013 account on iOS for iPhones or iPads.
An active Microsoft Exchange 2013 account.
An iPad or iPhone with iOS version 11 or higher. Due to an error in earlier versions, Microsoft Exchange connection cannot be established with older iOS versions: If you are still using iOS 6.1.1 or an earlier iOS 6 version, please update your iPad or iPhone.
Go to the Settings of your iPhone or iPad.
Click on Passwords & Accounts.
Tap Add Account.
Select the account type Microsoft Exchange.
Enter your Exchange 2013 email address in the Email field.
Tap on Next.
Enter your password in the Password field.
Enter exchange.ionos.us in the Server field and make sure that nothing is entered in the Domain field.
Select which data (mail, contacts, calendar, reminders, notes) you want to synchronize and confirm with Save.
The Exchange 2013 account is now set up!