How to resolve: 550 5.7.520 – Access Denied: External Forwarding Not Allowed

This error indicates that the recipient's Microsoft 365 organization has disabled automatic email forwarding to external addresses. The most possible reason is that Microsoft disables external forwarding by default as a security measure to prevent data leakage and phishing attacks.
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If you receive a bounce message with this error code, please contact us via our live chat or email. We will be happy to help.
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