Managing personal Outlook.com account settings, security, and privacy
Hi @Neil Munro
I understand how frustrating it is that your Hotmail account was unexpectedly disconnected and now shows Error 400 when you try to reconnect it.
Error 400 usually means that Microsoft could not process the sign-in request. This can happen after multiple sign-in attempts or because of an issue with the app, device, browser, or network.
Please try the following:
- Wait for a while before trying again to avoid repeated sign-in attempts.
- Select Other ways to sign in and use another available verification method.
- Update or reinstall the Outlook app.
- Try reconnecting the account using another browser, device, or network.
- Confirm that you can sign in directly at Outlook.com.
If the issue continues, please use the Microsoft Sign-in Helper to identify and resolve the sign-in problem.
Please note that this is a user-to-user support forum. Moderators, contributors including external Microsoft employees cannot directly intervene in Microsoft product features or access back-end systems. Our role is limited to providing technical guidance on reported issues, requests, or ideas only.
Thank you for your understanding.
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