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Hi,
We have a exchange 2003 environment and want to move the mailbox to exchange online. If we need to migrate mailbox to EXO, it needs to:
As migrate exchange 2003 to 2010 may have problem and need to migrate mailbox 2 times (EX2003 > EX2010 > EXO). We have an idea (option 2) that just export the exchange 2003 mailbox and create mailbox in EXO:
So, if option 2 is work, do we need to setup a new exchange 2016 for EXO mailbox management?
As if setup exchange 2016 is necessary for the management, we need to decommission exchange 2003 and then setup a new exchange 2016 server for hybrid.
Thanks
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Hi @Chong,
Welcome to the Microsoft Q&A platform!
According to your questions and concerns, I have following to share with you.
The option one is traditional way to migrate, and as you mentioned, it is complex and time-consuming and the options 2 is workable based on the steps you offered.
Whether setup a hybrid environment, it depends if you need manage your users from on-premises and have a need for directory synchronization or password synchronization. Therefore, setting up Exchange 2016 is not strictly necessary for mailbox management in EXO if you proceed with Option 2. You could refer to How and when to decommission your on-premises Exchange servers in a hybrid deployment | Microsoft Learn for more information.
But if you have a need for hybrid, it is recommended to have an Exchange 2016 or 2019 instead of Exchange 2003 because 2016 or 2019 have better support and compatibility with Exchange Online.
If the answer is helpful, please click "Accept Answer" and kindly upvote it and if you have anything else need help with me, please feel free to contact me.
For the option 2, the user account are sync from AD to Exchange online, then assign license to create mailbox.
When we setup exchange 2016 hybrid, do the exchange online mailbox can manage in exchange 2016 server directly? Or we need to perform "soft match", "hard match" or anything else?
Hi,
Assuming you have already moved mailboxes to Exchange Online and want to set up Exchange 2016 for hybrid management.
Please ensure Azure AD Connect is synchronizing users correctly and the primary SMTP addresses match between on-premises and Exchange Online.
If there are any discrepancies, resolve them either through soft matching or hard matching. Generally, soft matching (adjusting email addresses) should suffice if email addresses are consistent, and hard matching (using 'ImmutableID') is an alternative if needed.
Then you should be able to manage your Exchange Online mailboxes from the Exchange 2016.
If the answer is helpful, please click "Accept Answer" and kindly upvote it.
See, you can do with both options but it depends upon if you need Exchange 2016 or not.
You need to setup Exchange 2016 if you want to manage Exchange Online mailboxes from on-premises. But if you can manage everything directly through EXO there is no need for hybrid functionalities.
If we compare, then direct migration with PST is simpler to option 1 which is more complex due to multiple migration.