Smtp relay client smtp submission or direct send.
Office 365 smtp relay sent items.
As a result the sender s office 365 display name will now be shown as part of the from address.
Exchange is simply told to accept emails from the connection and relay them onward to the target so no you cannot in exchange at least see it in the traditional way of a sent items folder.
Opting for an office 365 smtp relay has the additional benefits of not requiring a separate licensed office 365 mailbox to send.
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If some or all of your mailboxes are in office 365 there are a few options available.
Microsoft 365 or office 365 smtp relay is very similar to direct send except that it can send mail to external recipients.
And are willing to share.
When you send emails through an office 365 connector it is relayed through office 365.
Due to the added complexity of configuring a connector direct send is recommended over microsoft 365 or office 365 smtp relay unless you must send email to external recipients.
I have exact same frustrating situation.
Messages that are sent by using smtp authenticated submission protocol will now behave in the same way as other submission protocols in office 365 such as the protocol that is used when emails are sent by using outlook on the web.
If you need assistance with a task or if you are troubleshooting a problem you might find the following articles helpful.
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