The mail sender could not send an outbound email. This failure indicates a misconfiguration either with the mail server or ...

The mail sender could not send an outbound email.  This failure indicates a misconfiguration either with the mail server or with the specific mail.  Frequent, repeating instances of this event indicate a failure with the mail server.  If this event occurs alongside event 12, then this event indicates a failure with Exchange. Infrequent instances of this event indicate misconfiguration of individual emails.

The mail server address is incorrect or specific outbound email has invalid data.

Ensure that the mail sender is configured to connect to the correct mail server and that the outbound mail has correct email addresses.
 
The specific exception reported by the mail server:
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