If you recently completed a transition from Exchange 2003 to Exchange 2007, you probably noticed that some of the migrated mailboxes are marked as Legacy Mailboxes. This can also happen during the co-existence period if you create Exchange 2007 mailboxes through the Exchange 2003 extensions to the Active Directory Users and Computers console.
In order to convert these mailboxes to regular mailboxes, run the following PowerShell cmdlet:
- Set-Mailbox -Identity -ApplyMandatoryProperties
In order to bulk convert several mailboxes:
- Get-Mailbox | where {$_.RecipientTypeDetails -eq "legacymailbox"} | Set-Mailbox -ApplyMandatoryProperties