I tried to add an email address to our existing domain. When I tried to validate the email ,this is the message I received.... "You have both Office 365 and previously existing accounts on your domain" It states that need to start directing emails to Office 365 and that we will no longer be able to send and receive with previous emails in this domain. What does this mean?
It's explaining that you can't use two different email services with your domain name. Once you setup Office 365 emails and start using them, any email addresses not setup in Office 365 will not work. For example, if you were previously using email with another provider or if you were using Workspace Email, those emails would stop working.