No. You must send your mail through a machine that:

 - runs an SMTP server
 - is willing to relay your outgoing mail

The second of these normally restricts you to your LANs (or ISPs) mail
server.

You can also relay through the mail server that corresponds to the
recipient of each mail, but that makes your client unnecessarily
complex, since it needs to do much of the transport job normally done
by the mail server (for example, it would need to determine the
correct recipient server, and handle transient errors properly). I
don't recommend this approach.

/gordon

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