Update for my previous question

Sadeen AlBasha 0 Reputation points

I thought I should share the whole error message:

((((PLEASE CHECK YOUR EMAIL ACCOUNT SETTINGS:- The SMTP server requires a secure connection or the client was not authenticated. The server response was: 5.7.57 Client not authenticated to send mail. Error: 535 5.7.139 Authentication unsuccessful, the request did not meet the criteria to be authenticated successfully. Contact your administrator. [LO6P123CA0040.GBRP123.PROD.OUTLOOK.COM 2023-11-29T13:34:13.969Z 08DBE596CF3F5738]))))

Thank you,

A family of Microsoft email and calendar products.
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  1. SokiGuo-MSFT 25,741 Reputation points Microsoft Vendor

    Hi @Sadeen AlBasha

    Welcome to our forum! Please kindly understand that the Outlook tag here we mainly focus on general issues about Outlook desktop client. For better research, please provide more information about this case:

    What did you refer to in your previous question?

    What is your account type (POP/IMAP/Exchange)?

    What are you doing when you get this error?

    Based on my search for error codes, here are links to several possible causes for this issue:

    Error: Authentication unsuccessful.

    Please also have a check if the security default is enabled in the tenant.

    Hope this helps!

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