In this series of posts I will show you the changes needed to migrate email services from a POP3 provider to Office 365. The client that I did this for had a number of issues that required us to migrate slowly; having both services up and running at the same time. This posed a number of issues as the MX record could not be changed until the end of the migration and all email had to flow into the POP3 provider first.

The technical issues occur when you have users on the legacy email sending and replying to email to the Office 365 users and vice versa. I have created a flow chart to show you the email flow between internal users and external email sources. There are a number of steps that need to be followed in order for this setup to work. It relies on the POP3 service to be able to forward email without intervention and modifications on the AD account to add an additional email alias on the user account.

For this client they had the full Enterprise Deployment. (ADFS Servers, ADFS Proxy Servers and a Directory Synchronization Server)

Series of Posts

1. Advanced Email Migration to Office 365 from a POP3 Service Provider – Part 1
2. Office 365 and DNS Setup for the Transition Email Domain – Part 2
3. Adding an Email Alias to an AD Account and Syncing Changes to Office 365 – Part 3
4. POP3 Email Forwarding to Office 365 – Part 4
5. Client Setup and Data Migration – Part 5

Thanks for visiting and reading my posts. I am always looking for more ideas. Please comment or email me with what you would like to see.

Kelsey Epps

Office 365 MVP