Hello. You can try adding the account using the Windows Mail configuration panel instead of Outlook’s built-in “Add Account” wizard. In some cases, the Control Panel method is able to create the Outlook data file correctly when the in-app setup fails.
Please try this:
- Close Outlook completely.
- Press Win + R, type control, and press Enter.
- In Control Panel, search for Mail and open Mail (Microsoft Outlook).
- Click Email Accounts > New.
- Choose Manual setup or additional server types and follow the prompts for your account type (Microsoft 365, IMAP, or POP).
Let me know if it works or if the same message still appears.