Using Classic Outlook on Windows for personal email, calendar, and contact management
Hi Howard Barker,
Based on the information shared, it appears the mailbox itself is accessible through Outlook on the web and works correctly on another Windows 11 device. This suggests the account credentials are likely valid, and the issue may be related to the Outlook profile, authentication components, or local connectivity on the affected desktop.
You may want to try the following:
1, Create a new Outlook profile:
- Open Control Panel > Mail > Show Profiles.
- Select Add, create a new profile, and configure the account again.
- Set the new profile as the default and test Outlook.
2, Clear stored Office credentials:
- Open Credential Manager > Windows Credentials.
- Remove any Outlook, Office, Exchange, or Microsoft 365 related entries.
- Restart the PC and try adding the account again.
3, Verify connectivity and authentication:
- Temporarily disable any third-party security software or web filtering tools.
- Ensure the system date, time, and time zone are correct.
- Test the account setup while connected to a different network if possible.
4, Repair Office:
- Go to Settings > Apps > Microsoft Office 2016 > Modify.
- Run a Quick Repair first, then an Online Repair if needed.
Since the same account works successfully on another device and through Outlook on the web, comparing the desktop's Outlook configuration and security settings with the working laptop may help identify the difference more quickly.
I hope this helps point you in the right direction. Let me know if you need further assistance, feel free to ask me by clicking "Add Comment" or "Add Answer" if you cannot add comment so your response will be visible. Thanks for your effort.
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