Symptoms & Diagnosis
The “Microsoft Word repeated sign in prompt” is a common issue where the application fails to cache your authentication token. Even after entering the correct username and password, the login window reappears almost immediately or upon the next launch.
This loop typically indicates a conflict between the local Windows Credential Manager and the Microsoft 365 authentication service. You may also notice “Account Error” warnings in the top right corner of the Word interface, indicating that your “Login Failed” status is persistent.
Common triggers include expired security tokens, conflicting work and personal accounts, or a corrupted Office identity folder in the local AppData directory.
Troubleshooting Guide
To resolve the login loop, follow these systematic steps. We recommend starting with the least intrusive method before proceeding to registry or folder modifications.
| Method | Primary Action | Success Rate |
|---|---|---|
| Credential Cleanup | Remove “MicrosoftOffice16” entries from Control Panel. | High |
| Account Disconnect | Remove account from Windows Settings > Accounts. | Medium |
| Identity Reset | Clear the Office Identity registry subkeys. | High |
Step 1: Clear Windows Credentials
Close all Office applications. Open the Control Panel and navigate to **User Accounts > Credential Manager**. Select **Windows Credentials**.
Locate all entries starting with `MicrosoftOffice16_Data:ADAL` or `MicrosoftOffice16_Data:SSO`. Expand each one and click **Remove**. This forces Word to generate a fresh authentication token during your next sign-in attempt.
Step 2: Use PowerShell to Clear Identity Cache
If the manual cleanup does not work, you can use a script to target the cached identity folders. Run the following command in an administrative terminal:
# Clear the Office Identity cache to fix login loops
Remove-Item -Path "$env:LOCALAPPDATA\Microsoft\Office\16.0\Licensing" -Recurse -Force
Remove-Item -Path "$env:LOCALAPPDATA\Packages\Microsoft.AAD.BrokerPlugin_*" -Recurse -ForceStep 3: Disconnect Work or School Accounts
Windows often tries to use “Seamless Single Sign-On” with accounts linked at the OS level. Go to **Settings > Accounts > Access work or school**.
Find the account causing the prompt, click **Disconnect**, and then restart Word. You can sign back in directly within the app without linking the account to the entire Windows operating system.
Prevention
To prevent the “Word Login Failed” error from recurring, ensure that your Office suite is always updated to the latest version. Microsoft frequently releases patches for the Authentication Library (ADAL).
Avoid using multiple Microsoft accounts for the same Windows profile if possible. When prompted to “Allow my organization to manage my device” during login, select “No, sign in to this app only” to prevent the OS from hijacking the credentials.
Finally, ensure your system clock is synchronized. An incorrect system time can cause security certificates to appear invalid, triggering constant re-authentication requests.