The mailbox database 'ABC_100MB' cannot be deleted

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Microsoft Exchange Error
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The mailbox database 'ABC_100MB' cannot be deleted.

Get-Mailbox -Database ABC_100MB
Failed
Error:
This mailbox database contains one or more mailboxes, mailbox plans, archive mailboxes, or arbitration mailboxes. To get a list of all mailboxes in this database, run the command Get-Mailbox -Database .


To get a list of all mailbox plans in this database, run the command Get-MailboxPlan. To get a list of archive mailboxes in this database, run the command Get-Mailbox -Database -Archive.

To get a list of all arbitration mailboxes in this database, run the command Get-Mailbox -Database -Arbitration.


 To disable a non-arbitration mailbox so that you can delete the mailbox database, run the command Disable-Mailbox .



To disable an archive mailbox so you can delete the mailbox database, run the command Disable-Mailbox -Archive. Arbitration mailboxes should be moved to another server; to do this, run the command New-MoveRequest . If this is the last server in the organization, run the command Disable-Mailbox -Arbitration -DisableLastArbitrationMailboxAllowed to disable the arbitration mailbox. Mailbox plans should be moved to another server; to do this, run the command Set-MailboxPlan -Database .


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[PS] C:\Windows\system32>Get-Mailbox -Arbitration -Database "ABC-1GB"

Name                      Alias                ServerName       ProhibitSendQuota
----                      -----                ----------       -----------------
SystemMailbox{1f05a927... SystemMailbox{1f0... ABC-mb-01        unlimited
SystemMailbox{e0dc1c29... SystemMailbox{e0d... ABC-mb-01        unlimited
FederatedEmail.4c1f4d8... FederatedEmail.4c... ABC-mb-01        3 MB (3,145,728 bytes)
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Get-Mailbox -Arbitration -Database “ABC-1GB”| New-MoveRequest -TargetDatabase “ABC_100MB”
You may get an error like:

Connect to ADSI edit:
Change values as below:



Refference:
http://www.oostdam.info/index.php/sectie-blog/46-verschillendesoftwareproducten/329-federatedemail-mailbox-error-on-move