Ran these commands on the Exchange Online server. Very strange. It doesnt see the Mailbox1 public folder I created for migration, but wont let me add it again....
PS C:\Users\scampbell> (Get-OrganizationConfig).RootPublicFolderMailbox | fl
IsValid : False
CanUpdate : True
HierarchyMailboxGuid : 00000000-0000-0000-0000-000000000000
LockedForMigration : False
PS C:\Users\scampbell> Get-Mailbox -PublicFolder | where {$_.IsRootPublicFolderMailbox -eq $true}
PS C:\Users\scampbell> Get-Mailbox -PublicFolder | where {$_.IsRootPublicFolderMailbox -eq $False}
PS C:\Users\scampbell> New-Mailbox -PublicFolder Mailbox1 -HoldForMigration:$true
Active Directory operation failed on DB4PR06A003DC05.EURPR06A003.prod.outlook.com. The object
'CN=Mailbox1,OU=Pulsion.onmicrosoft.com,OU=Microsoft Exchange Hosted
Organizations,DC=EURPR06A003,DC=prod,DC=outlook,DC=com' already exists.
+ CategoryInfo : NotSpecified: (:) [New-Mailbox], ADObjectAlreadyExistsException
+ FullyQualifiedErrorId : [Server=DBXPR06MB624,RequestId=7e5c129c-557f-4952-8646-8844049d28c7,TimeStamp=01/05/2015
13:08:13] [FailureCategory=Cmdlet-ADObjectAlreadyExistsException] 7F8EF522,Microsoft.Exchange.Management.Recipien
tTasks.NewMailbox
+ PSComputerName : pod51031psh.outlook.com