You can't use the domain because it's not an accepted domain for your organization.

Hello,
I am getting this error when user has this email domain.onmicrosoft.com.  it is complaining that it is not accepted domain....This domain domain.onmicrosoft.com as well as the other one domain.mail.onmicrosoft.com are both accepted domains in Office 365

Please advice.

You can't use the domain  because it's not an accepted domain for your organization.
    + CategoryInfo          : NotSpecified: (:) [New-MoveRequest], NotAcceptedDomainException
    + FullyQualifiedErrorId : [Server=BY2PR06MB534,RequestId=18eba3cd-5308-4e18-b50d-874d9a4e3a1c,TimeStamp=11/26/2013 7:44:46 PM] [FailureCategory=Cmdlet-NotAcceptedD
   omainException] FC8584B8,Microsoft.Exchange.Management.RecipientTasks.NewMoveRequest