Dear @Thomas Wilson,
Good day! Welcome to Microsoft Q&A forum!
Based on your description, I understand that you're unable to sign in to one of your Outlook accounts on your new Dell Inspiron 15. You’ve used this email before without issues, but now the setup process keeps looping back to the password screen. You’ve already tried factory resets, reinstalling Outlook, updating the PC, and using the web version, which reports that the account doesn’t exist. You also checked your domain provider but found nothing. You’re looking for a support phone number or a way to reach an actual person for help.
Thanks for taking the time to share what you've been experiencing and the troubleshooting so far.
At this point, the best next step is to contact Microsoft Support directly so they can take a closer look at the account and verify the backend configurations, and run any necessary synchronization tools to resolve the problem. If the issue requires further attention, they can escalate it to a specialized team for deeper analysis.
You can reach support through the Microsoft 365 Admin Center > Support > Help & support to create a support ticket (if you have admin access).
For more details, you could refer to this article: Get support for Microsoft 365 for business
You can also reach out to Phone support again. To get to a live support agent, please be noted that: Sometimes, you would hear the computer-generated voice at first, please kindly wait for it to end, and if an agent is available, you would be directed to them and get your support. Depending on your country or region, when you call the support number, you may hear an introduction of about 30 seconds such as "You can visit the link...". You can ignore this introduction and wait until you are presented with the options. Then press "1" as a business email user, and again "1" for technical help.
Thank you for your time and understanding!
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