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Create a New Mailbox for an Unassociated User ID

Applies to: Office 365 for professionals and small businesses, Office 365 for enterprises, Live@edu

Topic Last Modified: 2011-11-23

When you delete mailboxes in a cloud-based organization, you may end up with user IDs that aren't associated with a mailbox. This happens under the following circumstances:

In Microsoft Office 365, when you delete a mailbox
In Microsoft Live@edu, when you delete a mailbox and keep the Windows Live ID

However, you can create a new mailbox and attach the unassociated user ID to it using Windows PowerShell.

Before you begin

To learn how to install and configure Windows PowerShell and connect to the service, see Use Windows PowerShell in Exchange Online.
Verify that the user ID is in one of the accepted domains of your cloud-based organization. For more information, see Accepted Domains.

Create a new mailbox and attach an existing Windows Live ID in Live@edu

Run the following command:

Copy

New-Mailbox -Name <name> -WindowsLiveID <Windows Live ID> -UseExistingLiveId

For example, a user named Tamara Johnston has the Windows Live ID tjohnston@contoso.edu without a mailbox. To create a new mailbox for Tamara and associate her Windows Live ID with the new mailbox, run the following command:

Copy

New-Mailbox -Name "Tamara Johnston" -WindowsLiveID tjohnston@contoso.edu -UseExistingLiveId

Create a new mailbox and attach an existing user ID in Office 365

Run the following command:

Copy

New-Mailbox -Name <name> -MicrosoftOnlineServicesID <user ID> -UseExistingMicrosoftOnlineServicesID

For example, a user named Tamara Johnston has the user ID tjohnston@contoso.com without a mailbox. To create a new mailbox for Tamara and associate her user ID with the new mailbox, run the following command:

Copy

New-Mailbox -Name "Tamara Johnston" -MicrosoftOnlineServicesID tjohnston@contoso.com -UseExistingMicrosoftOnlineServicesID

Things to consider

You can't use this procedure on a user ID that's already associated with a cloud-based mailbox or mail user.
These procedures don't replace any of the existing properties of the user ID, such as first name, last name, name, or password. These procedures simply associate an existing user ID with a new mailbox.
In Live@edu, to learn how to remove a mailbox and keep the associated Windows Live ID, see the following topics:
- Delete a Mailbox
- Options for Deleting Mailboxes in Windows PowerShell in Live@edu
In Live@edu, this procedure doesn't work with Windows Live IDs that were created in the domain before the domain was enrolled in Live@edu. To learn about how to import or evict these Windows Live IDs, see Import or Evict Existing Windows Live IDs in Live@edu.
You can also create a new mail user for an unassociated user ID. For more information, see Create Mail Users.