Emails created in CRM are sent using the outgoing email method specified on the account of the user creating the email. Only one outgoing method can be set for a user, the methods are to use the CRM client for Outlook or the Email Router (later versions
of CRM also have Server-side synchronization but that is not available for CRM 2011).
An email created in CRM can only be sent via one of the outgoing methods. Regardless of how it is sent, the email will be stored in CRM and linked to the record it was regarded to.
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