We currently have a POP email server and are going to migrate to Office 365 Online Exchange server. Our domain name points to our POP server provider and I want to make sure we don't lose emails and the transition is seemless.
Is it possible to allow emails to first come to the Exchange server and if there is no existing email account, then it will propagate to the old server?
What is the best way to make sure we don't lose any emails or that we are transitioning to Exchange without any loss. How would I setup the MX records to avoid loss?