Unable to sign in with school email on outlook app

Hi Jayden,

Thank you for providing the screenshot.

Based on the image, the prompt you are seeing does not appear to be the standard Microsoft 365 modern sign-in page. Since you can successfully access Outlook on the web with your new university password, the account and password themselves are likely working correctly.

The issue is more likely related to cached Windows credentials, New Outlook app data, or a VPN/proxy/security filter interfering with authentication.

Please try the following steps:

1/ Cancel the credential prompt

Instead of repeatedly entering your password, select Cancel. A normal Microsoft 365 sign-in should redirect you to your university's Microsoft sign-in page, which may also require multifactor authentication.

Then:

• Close New Outlook completely.
• Press Ctrl + Shift + Esc to open Task Manager.
• End any remaining Outlook (new) or Microsoft Outlook processes.
• Restart Windows and try opening Outlook again.

2/ Rule out network or proxy interference

The address shown in the prompt suggests Outlook may be receiving a credential challenge from a network proxy or filtering service instead of the expected Microsoft sign-in flow.

Temporarily:

• Disconnect any VPN connection.
• Go to Settings > Network & Internet > Proxy.
• Disable Use a proxy server unless it is required by your university.
• Test using a different network, such as a mobile hotspot.
• If you use third-party antivirus software with HTTPS/web scanning, temporarily disable that feature and test Outlook again. Re-enable it afterward.

Note: If this is a university-managed device, do not disable any security controls without approval from your IT department.

3/ Remove outdated saved credentials

Since the problem started after changing your password, Windows may still be using an old cached credential.

Close Outlook.

Open Credential Manager.

Select Windows Credentials.

Look for entries related to:

• Your university email account
• Outlook
• Microsoft 365
• Microsoft Office
• ADAL
• OneAuth
• Your university sign-in domain

Remove only the entries associated with the university account.

Restart Windows and try signing in again.

Reference: Credential Manager in Windows | Microsoft Support

4/ Repair or reset New Outlook

Go to:

Settings > Apps > Installed Apps > Outlook (New) > Advanced Options

• Select Repair first.
• If the issue persists, select Reset.

Please note that resetting Outlook will remove local app settings, and you may need to add the account again. Your mailbox data remains stored in Microsoft 365 and will still be accessible through Outlook on the web.

5/ Remove and re-add the account

After repairing or resetting Outlook:

• Open New Outlook.
• Go to Settings > Accounts > Email Accounts.
• Remove the university account if it is listed.
• Restart Outlook.
• Add the university email address again.
• Complete the normal Microsoft 365 sign-in process and any MFA prompts.

Do not manually configure POP or IMAP unless directed by your university.

6/ Check the Windows work or school account connection

Open:

Settings > Accounts > Access work or school

• Select the university account.
• Choose Info or Fix if available.
• If Windows offers a Fix option, run it.

Note: If this is a university-managed computer, do not disconnect the account, as doing so may remove device management policies, certificates, or network access.

If the issue continues:

Please contact your university IT help desk and provide:

• The screenshot of the prompt
• Confirmation that Outlook on the web accepts the new password
• Whether Outlook works while connected to a mobile hotspot
• Whether a university VPN or proxy is installed
• The approximate time the sign-in attempts failed

Ask them to review the account's sign-in logs, Conditional Access policies, proxy/web-filter configuration, and whether the device's work or school registration needs to be refreshed following the password change.

I hope these suggestions point you in the right direction and help get Outlook working again soon. If you need any additional assistance, please feel free to contact me.

Thank you for your patience and understanding. Wishing you a great day ahead.

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