cannot reach external distribution emails

Question

experiencing an issue affecting one user in our organization when sending emails to external distribution lists.

Specifically, when this user sends an email to distribution list addresses that belong to domains outside our organization, the message is not delivered. Instead, the sender receives a delivery failure notification, and the external distribution list never receives the message.

This problem:

Occurs only with one specific user in our tenant

Happens with multiple external distribution lists across different domains

Does not affect other users in our organization, who can send to the same distribution lists without any issue

Answer 1

Hi Francesca,

It seems some sort of User attributes on the user object? Please compare user attributes with other working user and confirm licences are same, any exclusions or Exchange policies that might impact the user sending email?

Can you copy the user to new user and test same process ? Recreate new user and allow to send mail?

Hope this helps.

JS

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