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Article ID: 2666578 - Last Review: December 12, 2014 - Revision: 17.0


You try to add a subdomain to an existing domain in a Microsoft cloud service such as Office 365, Microsoft Intune, or Microsoft Azure by using the New-MSOLDomain cmdlet. However, you receive the following error message:
New-MsolDomain: Unable to add this domain. It is a subdomain and its authentication type is different from the authentication type of the root domain.


This issue occurs if you try to use the New-MSOLDomain cmdlet to add a subdomain to an existing domain that's set up for federated authentication. The New-MSOLDomain cmdlet tries to add the subdomain as a standard authentication domain.


To add a subdomain to a domain that's set up for federated authentication, follow these steps:
  1. Connect to Azure Active Directory (Azure AD) by using Windows PowerShell. For more info, go to the following Microsoft website:
    Connect to Azure AD Using Windows PowerShell (
  2. Use the New-MSOLFederatedDomain cmdlet.

    The syntax to add a subdomain is as follows, where <subdomain> is the name of the subdomain that you want to add:
    New-MSOLFederatedDomain -DomainName:<subdomain>


For more info about how to use Windows PowerShell to manage Azure AD, go to the following Microsoft website:

Still need help? Go to the Office 365 Community ( website or the Azure Active Directory Forums ( website.

Applies to
  • Microsoft Azure cloud services
  • Microsoft Azure Active Directory
  • Microsoft Office 365
  • Microsoft Intune
  • CRM Online via Office 365 E Plans
  • Microsoft Azure Recovery Services
  • Office 365 User and Domain Management
  • Office 365 Identity Management
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