- The username parameter of the impersonating account is defined in user principal name (UPN) format. However, the Active Directory trust type doesn't support UPN suffix routing.
- UPN suffix routing for a particular suffix is disabled for the trust.
New-Object -TypeName Microsoft.Exchange.WebServices.Data.WebCredentials("SamAcctName", "Password", "NetBIOSDomain")
Office 365 Dedicated allows for a highly customized configuration for Active Directory trusts between the on-premises Active Directory forests and domains and the customer's Office365 Dedicated Active Directory forest. Be aware that UPN suffix routing is supported only over forest level trusts. UPN suffix routing isn't supported over external/domain level trusts. In some cases, UPN suffix routing may be disabled for a particular UPN suffix, even over a forest level trust.
For more information about UPN suffix routing across Active Directory trusts, see Routing name suffixes across forests.
Article ID: 2933452 - Last Review: 12 Feb 2014 - Revision: 1