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some users whose mailboxes are present both on-prem (Exchange) and Exchange Online (O365). And as a result of this, such affected user sees different emails when logged in either with the on-prem link or with the outlook O365 link.
Can such account be merged as one?
@JustinMicheal-7973
You cannot merger those mailboxes content directly. You need to backup Exchange online mailbox content, then clean Exchange online mailbox object:
Connect-ExchangeOnline
Set-User user@domain.onmicrosoft.com -PermanentlyClearPreviousMailboxInfo
In this way, those two mailboxes will be connected. You can import data to the Exchange on-premises mailbox.
For more detailed information, you could have a look about this article: A user has one mailbox in Office 365 and one in an on-premises Exchange
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There are around 20000 mailboxes I have been advised to do bulk PST export/import
please help me with the detailed steps on the same
I want to merge duplicate user account (On-Prem and O365)
some users whose mailboxes are present both on-prem (Exchange) and Exchange Online (O365). And as a result of this, such affected user sees different emails when logged in either with the on-prem link or with the outlook O365 link.
10000 users, at the moment are affected. It’s a re-occurring situation, but randomly happens when a new user is created
Can i try to Bulk export/import via the PST ingestion tool and check. If yes how need some detailed steps and explanation
In Exchange online, you cannot export data from mailbox directly(It is different from Exchange on-premises). You could use "New-MailboxSearch" to search all content from mailbox, then export data.
About third-party tools, due to our policy, we cannot test and recommend to you. You could send an email to inform users in your organization to export data from Outlook client to pst directly. Then they can also import data to from Outlook to new mailbox.
Please help me with the detailed commandlets/steps for the same so that it would be of help
For a single user how can i perform the same
Could you please help me with the steps
If you doesn't familiar with PowerShell command, I would suggest you create request from GUI:
You could create search for one or multiple mailboxes. Personally, I think export/import from Outlook is more convenient, because it split task to each user.
I am writing here to confirm with you any update about this thread now?
If the above suggestion helps, please be free to mark it as an answer for helping more people.