Office 365 email migration

Hi Experts,

Did anyone know what is the migration process from blue host to office 365? Please share with me best resource if available . I am kind of new to the office 365 /Blue host migration.

Thank you in advance
Jey_PIT Security Eng Asked:
Who is Participating?

[Product update] Infrastructure Analysis Tool is now available with Business Accounts.Learn More

I wear a lot of hats...

"The solutions and answers provided on Experts Exchange have been extremely helpful to me over the last few years. I wear a lot of hats - Developer, Database Administrator, Help Desk, etc., so I know a lot of things but not a lot about one thing. Experts Exchange gives me answers from people who do know a lot about one thing, in a easy to use platform." -Todd S.

Alessandro ScafariaInfrastructure Premier Field AdministratorCommented:
You may follow these steps:

1. Perform this step-by-step guide to correctly put Office 365 side-by-side into your environment:

2. Point MX records to Office 365 to make inbound mail flow directly to Office 365.

3. Remove the previous MX records to avoid any potential mail flow issues.

4. About your mailboxes left at Blue Host, you can either leave them as previous backups or just delete them because new mailboxes and mail flow are hosted at Office 365.

I hope it helps......
Jey_PIT Security Eng Author Commented:
Thank you for your comment . Could you please advice, How is that possible to bring up the old mailbox to new office 365 environment ? Client need all mailbox and mail in office 365.

Also, Is it possible to rollback this change .

Thank you in Advance .

Alessandro ScafariaInfrastructure Premier Field AdministratorCommented:
In that link I provided you above, there is a real world example scenario in which you may notice that only 2 mailboxes were brought into Office 365 for testing.......

You may roll back of course.......Does you client download emails into Outook clients at the moment?

Step 6: Set up email forwarding at your current provider

At your current email provider, set up forwarding for Margie and Mike's email accounts to your domain:

Margie's A. Datum mailbox should forward to
Mike's A. Datum mailbox should forward to
When you complete this step:

All mail sent to and will be available in Office 365.
When Margie and Mike reply to mail they receive, the Reply-to address will be and

Contact your current email provider for the exact steps for setting up forwarding.
You don’t need to keep a copy of messages at the current email provider.
Most providers forward email leaving the Reply-to address of the sender intact, so that replies go to the original sender.

Step 7: Test mail flow

Sign in to Outlook Web App (OWA) using Margie’s credentials. The URL is
Perform the following tests:
Test local Office 365 email. For example, send an email to Mike ( This email should be delivered immediately. In this scenario, the message will not be routed to Mike’s mailbox on A. Datum because Office 365 sees the mailbox as being local.
Test email to someone who's on the other email system. For example, send an email to Sue. This email should be delivered to Sue’s mailbox on the A. Datum server.
From an outside account, or from an employee'e email account on the other email system, verify that forwarding is set up properly on the other email system. For example, from Sue’s A. Datum account or a Hotmail account, send Margie an email and verify that it arrives in Margie’s Office 365 mailbox.

Step 8: Move mailbox contents

Since there are only two users to move, and since Margie and Mike are both using Outlook today, the email can be moved by opening the old .PST file in the new Outlook profile and copying the messages, calendar items, contacts, etc. Once organized in the proper locations in the Office 365 mailbox, the items can all be accessed from any device, anywhere.

When more mailboxes are involved, of if the employees are not already using Outlook, you can use the migration tools available in the Exchange admin center. To get started, go to the Exchange admin center, and follow the directions in Migrate Email from an IMAP Server to Exchange Online.

Experts Exchange Solution brought to you by

Your issues matter to us.

Facing a tech roadblock? Get the help and guidance you need from experienced professionals who care. Ask your question anytime, anywhere, with no hassle.

Start your 7-day free trial
It's more than this solution.Get answers and train to solve all your tech problems - anytime, anywhere.Try it for free Edge Out The Competitionfor your dream job with proven skills and certifications.Get started today Stand Outas the employee with proven skills.Start learning today for free Move Your Career Forwardwith certification training in the latest technologies.Start your trial today
Office 365

From novice to tech pro — start learning today.