Attach and detach of mailbox

Thanks Jake

Could you provide the steps involved for a minimal migration?

Hi @Reggie,

Certainly! Here are the steps for a Minimal Hybrid Migration from Exchange 2016 to Office 365:

1. Prepare Your Environment

• Ensure your domain is verified in Office 365.
• Make sure your Exchange 2016 server is up to date with the latest cumulative updates and patches.

2. Set Up Directory Synchronization

• Download and install Azure AD Connect on your on-premises server.
• Configure Azure AD Connect to synchronize your on-premises Active Directory with Azure AD.

3. Configure Hybrid Configuration

• Use the HCW to establish a hybrid configuration between your on-premises Exchange and Office 365.
• Ensure that mail flow and free/busy information are working correctly between on-premises and Office 365.

4. Migrate Mailboxes

• In the Exchange Admin Center (EAC), create migration batches for the mailboxes you want to move.
• Start the migration batches. Mailboxes will be synchronized to Office 365 while still being accessible on-premises.
• Once the initial synchronization is complete, finalize the migration for each batch.

5. Update your DNS records to point to Office 365. This ensures that mail flow is directed to Office 365 and that clients can locate their mailboxes.
6. Decommission On-Premises Exchange (Optional)

• Ensure all mailboxes and services are functioning correctly in Office 365.
• If you no longer need your on-premises Exchange server, you can decommission it after verifying that everything is working as expected in Office 365.

Notes:

1. Perform the migration during non-peak hours to minimize impact on users.
2. Inform users about the migration schedule and any expected downtime.
3. Keep an eye on the migration process and be ready to address any issues that arise.

Please feel free to contact me for any updates. And if this helps, don't forget to mark it as an answer.

Best,

Jake Zhang

Thanks, could you also provide the detailed steps to detach a mailbox and attach the new O365 mailbox?

Hi @Reggie,

Certainly! Here are the detailed steps to detach a mailbox from Exchange 2016 and attach it to a new Office 365 mailbox:

1. Export Mailbox to PST

• Open Exchange Admin Center (EAC).
• Go to Recipients > Mailboxes.
• Click on More Options (...) > Export to a PST file.

2. Detach the Mailbox

• In the EAC, go to Recipients > Mailboxes, select the mailbox, and click on More Options (...) > Disable. This will detach the mailbox from the user account but keep the data in the database.
• If you want to completely remove the mailbox, you can use the Remove option instead of Disable.

3. Create a New Office 365 Mailbox

• Navigate to the Office 365 Admin Center.
• Click on Add a user to create a new mailbox.
• Enter the required information to create the new mailbox.

4. Import PST to Office 365 Mailbox

• Use the Office 365 Import Service to upload the PST file. You can do this via the Security & Compliance Center.
• Navigate to Data governance > Import.
• Follow the prompts to create a new import job and upload the PST file.
• Once the PST is uploaded, map it to the new Office 365 mailbox.

5. Verify Mailbox and Update DNS Records

• Ensure that the new Office 365 mailbox is functioning correctly and that all data has been imported.
• Update your DNS records (Autodiscover and MX records) to point to Office 365 to ensure proper mail flow.

Please feel free to contact me for any updates. And if this helps, don't forget to mark it as an answer.

Best,

Jake Zhang

Hi @Reggie,

Please kindly consider this comment as a warm follow up, I want to know if your problem has been solved. If you still have any other questions, please feel free to comment here and I'm glad to provide further support.If the above info is helpful to this question, you can click "Accept Answer". Have a nice day!

Best,

Jake Zhang