Office 365 User mailboxes treated as on-premises User mailboxes by Get-Mailboxstatistics

Question

Hello,

I have exchange hybrid in place. Some mailboxes are hosted in exchange server 2016 others are hosted in office 365.

When i run
Get-MailboxStatistics -database "DB01" | select displayname, totalitemsize | Export-CSV F:\temp\db01.csv

I get a list with combination of on-premises user mailboxes, some hosted in DB01 others hosted in office365. My expectation is to have the list of all mailboxes in DB01 returned only.

What i'm i doing wrong or what could be the issue?

Answer 1

@Benard Mwanza

For a migrated mailbox, there doesn't exist database attribute on Exchange on-premises, this command will not find Exchange online mailbox. So, I think it is a synced mailbox or an Exchange on-premises mailbox which use the same name as Exchange online mailbox.

I would suggest you use commands below to check whether this mailbox is an Exchange on-premises mailbox:

Get-Mailbox ThisUser  
Get-RemoteMailbox ThisUser  

You can also search from Exchange on-premises admin center to double check the type of this mailbox:

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