Rename a User ID

  • Article

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

In the cloud-based service, users are identified by their user IDs, which are formatted like e-mail addresses. A cloud-based user signs in to their mailbox using their user ID, and the user ID is also the user's e-mail address. Occasionally, an administrator needs to rename an existing user ID, for example, when a user's legal name or the organization's naming convention changes.

The user ID appears in the General section of the mailbox properties page in the Exchange Control Panel. However, you can't rename the user ID in the Exchange Control Panel. You have to use Windows PowerShell as follows:

  • Rename a Windows Live ID in Live@edu
  • Rename a user ID in Office 365
  • Things to consider

Before you begin

  • Make sure you understand the implications of renaming a user ID on the user's primary e-mail address. See Primary e-mail addresses.
  • To learn how to install and configure Windows PowerShell and connect to the service, see Use Windows PowerShell in Exchange Online.

Rename a Windows Live ID in Live@edu

In Microsoft Live@edu, the user ID is called Windows Live ID.

Run the following command:

Set-Mailbox <Identity> -WindowsLiveID <new Windows Live ID>

For example, to rename the user ID of an existing user named Kim Akers, who has the Windows Live ID kakers@contoso.edu, to kimakers@contoso.edu, run the following command:

Set-Mailbox kakers@contoso.edu -WindowsLiveID kimakers@contoso.edu

Rename a user ID in Office 365

Run the following command:

Set-Mailbox <Identity> - MicrosoftOnlineServicesID <new user ID>

For example, to rename the user ID of an existing user named Kim Akers, who has the user ID kakers@contoso.com, to kimakers@contoso.com, run the following command:

Set-Mailbox kakers@contoso.com -MicrosoftOnlineServicesID kimakers@contoso.com

Things to consider

  • Accepted domains   You can change the domain part of the user ID to any accepted domain that's already configured in your organization. For example, if your cloud-based organization uses contoso.edu and students.contoso.edu, you can rename a user ID from bob@students.contoso.edu to robert@contoso.edu. Learn more at Accepted Domains.
  • **Primary e-mail addresses   **By default, when you create a mailbox in the cloud, the user ID that you specify is also used as the primary e-mail address. The primary e-mail address is used as the From address when the user sends e-mail.
    However, you can change a user's primary e-mail address without changing their user ID as described in Change a User's Primary E-mail Address.
    What happens to the user's primary e-mail address when you rename the user ID?
    • If the user ID and primary e-mail address are the same, the primary e-mail address is changed to the same value as the new user ID. The user's original primary e-mail address is kept on the mailbox as a proxy address.
    • If the user ID and primary e-mail address are different, the primary e-mail address isn't changed. The user's original user ID and new user ID are kept on the mailbox as proxy addresses.
      What are proxy addresses? Learn more at Proxy Addresses.
  • Other attributes   Renaming the user ID can automatically update the primary e-mail address and the proxy addresses of the mailbox. However, other attributes that contain the user ID value aren't automatically updated when you rename the user ID. For example, if you use the user ID value for the Name attribute, the Name attribute isn't updated when you rename the user ID. Therefore, if you used the user ID value for other mailbox attributes, make sure to manually update those values after you rename the user ID.
  • Reusing a user ID   If you rename a user's user ID and plan to use the old user ID value for a different user's mailbox, be aware of the following issues:
    • You must manually remove the old user ID value from the proxy addresses of the existing user's mailbox. This will prevent the existing user from receiving any messages sent to the old user ID.
    • The new user with the reused user ID may receive messages intended for the original user. For example, if the original user subscribed to newsletters and mailing lists using their user ID for the e-mail address, those messages will be delivered to the new user's mailbox that's now associated with that user ID.