The following errors may occur when using the Microsoft Dynamics CRM Email Router with Office 365 Exchange Online:
"The user account which was used to submit this request does not have the right to send mail on behalf of the specified sending account."
"The access credentials that you have specified have insufficient delegate permissions to send the e-mail message. Contact your Microsoft Exchange administrator to grant the required Permissions."
These errors will occur when the Administrator user setup in the Outgoing Profile of the Microsoft Dynamics CRM Email Router does not have Send As or Delegate permissions on the mailbox being used to send the email. The Administrators and users in Office 365 Exchange Online by default do not have Send As or Delegate Access permissions.
To resolve this issue, the Administrator user setup in the Outgoing Profile of the Microsoft Dynamics CRM Email Router must be granted Send As permissions if Send As permission is marked. If Delegate Access is marked in the Outgoing Profile, Full Access permissions must be granted to the user for the mailbox, as Delegate access cannot be explicitly defined with Exchange Online. These are added with Windows Powershell.
To Connect Windows Powershell to the Exchange Online Service
To Grant Full Access Permissions
To Grant Send As Permissions