For Microsoft Exchange 2019
In this article, we'll show you how to use Microsoft Exchange 2019 with an existing email address.
In Microsoft Exchange 2019, it is no longer possible to create the account with an external or previously created email address in your account. It is required that you set up the Exchange account with a new email address. For more information, please see the Help Center article Setting Up Microsoft Exchange 2019 with a New Email Address.
However, there is the option to use your new Microsoft Exchange 2019 email address as the return address for messages sent to your existing address. We'll show you how to do this below.
Activate the POP/IMAP setting on your existing email address.
Configure your existing email account as an additional IMAP account in Outlook 2019 - alongside your new Microsoft Exchange 2019 account from 1&1 IONOS.
If you now receive an email that was sent to your existing email address, it will also be displayed in Outlook.
If you reply, you can select which account you want to use in the From field: If you select your new Microsoft Exchange 2019 account here, the email sent to your existing email address will be answered with your new Microsoft Exchange 2019 email address. You can find the From field in Outlook under Options > Show Fields > From
This way, you can share your new Microsoft Exchange 2019 email address with your contacts, while always having email from your existing email account at hand.