I can't send email to anyone

Question

Diagnostic information for administrators:

Generating server: GV1PR01MB8785.eurprd01.prod.exchangelabs.com

Remote server returned '550 5.1.8 Access denied, bad outbound sender AS(45005)

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Answer 1

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Hi @Xristina Asimakopoulou

Thank you for reaching out to our Q&A forum.

You are seeing this error and cannot send any emails because your account is not recognized as a valid sender. The fastest way to get this resolve is to contact your IT admin of your organization (if you are using school account, please reach out your school's IT admin) and give them this article:

NDR error code "550 5.1.8 Access denied, bad outbound sender" - Microsoft Support

The IT admin will be able to unblock your account from the back-end server, after your account released, all restrictions will be removed in 1 hour and you can start sending emails again.

I hope this information helps.

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