How To Remove ":CAUTION: This email originated from outside of the organization. Do not click links or open attachments unless you recognize the sender and know the content is safe."

Hello Joe Smith,

The “CAUTION: This email originated from outside of the organization” message is a security warning used by many organizations to help users identify emails received from outside their environment and reduce the risk of phishing or spoofing. The message is typically added by your email system when an email is received from a domain that’s not recognized as part of your organization.

In some cases, an internal email may also be marked as external because of the organization’s email configuration or because the sender is using a different email alias or domain. If you believe the message has been classified incorrectly, please contact your IT or email administrator and ask them to review the configuration under: Exchange Admin Center > Mail flow > Rules

For your reference: Organization-wide message disclaimers, signatures, footers, or headers in Exchange Online | Microso…

The administrator can check whether a mail flow rule is adding the warning and determine whether an exception should be created for a trusted sender or domain.

You can also try adding the sender to the Safe Senders list in Outlook. However, please note that this primarily affects junk email filtering and may not remove a warning applied by an organization-level mail flow rule.

Since the warning is intended as a precaution, please continue to verify the sender before clicking links or opening attachments, even when the email appears to come from a familiar source.

I hope this information helps clarify why the message appears and who can review the configuration.

Kind regards,