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A dynamic IP address isn’t supported or allowed. Obtain the public IP address you’re using on-premise. Configure Exchange Online to receive inbound Emails from other sources. For example, if the account that you’re relaying from is and you want to relay through (an Office 365 user), you have to add as an alternate email address You also need a virtual SMTP server running in your domain to relay mail to office 365, authenticating itself You need an SMTP incoming connector in exchange online to allow direct submission method of SMTP mail deliveryĪ.
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Any email address (including non-Office365 mailboxes) can send mail using an SMTP relay, as long as it uses a domain that’s set up as yours in Office 365.Ĭlient SMTP Submission: Client SMTP submission allows your device or LOB application to send emails using an email address associated with an Office 365 mailbox by authenticating itself using that account. SMTP Relay: An SMTP relay is used to send mail from your organization by authenticating the IP address or certificate of the sender.
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If some or all of your mailboxes are in Office 365, there are a few options available: SMTP relay, client SMTP submission, or Direct Send. SMTP (Simple Mail Transfer Protocol) is used when you set up an on-premises multi-function printer, scanner, fax, or line of business (LOB) application that needs to send email.
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