0x8004011D server unavailable error, and apparent conflict between Personal / Work/School accounts and tenant account

Hi Swalker,

I can understand how frustrating this must be, especially after spending hours troubleshooting and having four tickets closed without confirmation that the issue was resolved.

Before suggesting another support route, could you clarify where you submitted those four fault tickets, for example through the Microsoft Support contact page, the Get Help app, an AI assistant, or another channel? Did Microsoft provide a support case number for each ticket, and were you able to speak with a live support agent?

The 451 4.4.4 ATTR5 response is particularly important. It indicates that Exchange Online is treating the recipient’s domain as belonging to a hosted Microsoft 365 tenant that does not currently have a mail-enabled subscription. Since you are using Microsoft 365 Family and do not have a business administrator, this may require Microsoft to check the mailbox provisioning, domain association, and mail-routing status on the service side. However, the error alone does not confirm that your personal and work or school accounts are conflicting.

Please note that this is a user-to-user support forum. Community contributors and moderators cannot access account records, inspect tenant configurations, change mailbox provisioning, review backend mail routing, or reopen previously closed support cases.

The account lockout should also be treated as a separate issue. When you try to sign in, what exact error message or recovery option appears on the screen? Please do not post your email address, verification codes, recovery information, ticket numbers, tenant ID, or other account-specific details publicly.

If you still have access to the previous ticket confirmations, keep the case numbers, the complete non-delivery report, the code, and the diagnostic timestamp available. While my initial response may not fully resolve the issue, I truly appreciate your cooperation as we work together toward identifying the most effective solution. Thank you so much for your understanding.     

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Hi Vikki

Thank you for your answer, great to hear from you.

We have had the email address working for about 3 years with no problems and then it just stopped working. The support tickets have been lodged through the Microsoft Support contact page, and all other prompts from this page. We have kept the numbers but even these tickets are restricted in what category you can lodge a fault under. We did get one rep call us and then hung up on us when they could not help, We have even tried calling their advertising group as they have "real people" that you can talk to. But they could not help. I agree it appears that the fault is with the domain / exchange /server at their end. But the problem is that none of the support pages have a link that sends your ticket to the exchange/ domain/ server support team and all other support links and AI just tell us to go back to the administrator which we cannot do as we don't have one. There does not seem to be an escalation path to help with this, we did ask the one rep who we were talking to if they could send the fault ticket to the exchange / server team but it was then that they hung up on us. We have the information such as the diagnostic report etc but it is of no help to us as there is no one that we can send it to.??

Thanks again for reaching out and not sure what out next steps should be?