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PMDepending on where you encountered it, this file likely serves one of the following purposes: ⚙️ Digital Marketing Tool
Security tools and email providers use this header to verify if the "From" address matches the true originating server. Spot Spoofing Like the Pros - Biola University
An X-Sender header often identifies the actual email address or software used to send a message, which is useful for detecting email spoofing .