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LiquidFiles Documentation

When using Office 365 to relay emails, you need to use the setting "Use the Email Sender Address for all emails" configured in Admin → Configuration → Email:

images/system/email/email_sender_configuration.png

You then configure the email relay section as follows:

images/system/email/office365_relay.png

Please see further documentation for Office 365 at the Office 365 Relay Documentation.