Connecting to Exchange on-prem getting The remote server returned an error: (401) Unauthorized.
説明
When connecting to Exchange on-prem in On Demand Migration for Email (ODME) the connection is failing with "The remote server returned an error: (401) Unauthorized." when UserPrincipalName/SMTP is used.
対策
Domain\User for login should be used instead of UPN/SMTP login when establishing connection in ODME when the error is encountered.