The domain is already being used with another Microsoft hosted service, such as Office Live or Live@EDU, and a domain can be associated with only one service. Try one of these things:
The DNS settings for Microsoft Communications Online are not configured correctly. Add the records below to the DNS settings ...
The DNS settings for Office Communicator Online are not configured correctly. Add the records below to the DNS settings at ...
The domain already exists as a standard authentication domain. To convert the domain to identity federation, use convert-MSOLDomainToFederated. ...
The domain is already being used with a Microsoft Online Services Business Productivity Online Suite (BPOS) account and a ...
The domain is already being used with another Microsoft hosted service, such as Office Live or Live@EDU, and a domain can ...
The domain is part of a managed or federated namespace. The following users were not granted access to the site collection: ...
The domain name contains characters that are not valid. Type a domain name using only letters, numbers, hyphens, and periods. ...
The domain name for which the properties from both the Active Directory Federation Services 2.0 server and Office 365 will ...
The domain name system (DNS) translates easy-to-remember domain names, like www.microsoft.com, to IP addresses, like 192.168.255.255, ...