Office Microsoft 365 users receiving messages at their @mail.wvu.edu addresses may notice a red rectangle at the top of some messages containing the following alert message: "This sender failed our fraud detection checks and may not be who they appear to be."
This message is inserted by Microsoft Office 365 servers as a caution when messages appearing to have come from @mail.wvu.edu addresses are not sent directly to recipients at other @mail.wvu.edu addresses. It is common for this to appear when the sender's message goes through a third-party system before being delivered to an @mail.wvu.edu address. Microsoft uses this to advise that the sending address may not be genuine.
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