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MAILER-DAEMON - Unexpected Error Occurred: Email Validation Required

Monday, August 12, 2019 - 15:08

From: Microsoft <msa[at]
Sent: Monday, August 12, 2019 2:33 PM
To: User, Typical S (mst3k) <mst3k[at]>
Subject: MAILER-DAEMON - Unexpected Error Occurred: Email Validation Required


Sign in with your own domain | View it online


Office 365

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Making sign-in more secure by verifying your email

Mail Security Update, verify your Office 365 sign-in email securely as part of our protocol, it's easy and it will be set up automatically. Failure to do so will cause a temporary suspension of service until verification is done.



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Verifying that you're the owner of your custom domain is a multi-step process, but don't worry—there's plenty of help to get you through it. You can talk with a Microsoft support engineer who'll walk you through the process.

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