Troubleshooting Passwordless Sign-in Failures with Windows Hello

Passwordless sign-in failures with Windows Hello occur when Microsoft 365 apps fail to authenticate PIN, facial recognition, or fingerprint credentials against local Trusted Platform Module (TPM) security keys or Microsoft Entra ID. This failure surfaces as repeated PIN prompts, “Your credentials could not be verified” errors, or unexpected password fallback requests when launching Teams, Outlook, or Office desktop apps. It typically stems from corrupted Ngc container files on the local drive, desynchronized TPM biometric keys, or broken Web Account Manager (WAM) identity tokens following a Windows or firmware update.

Fast-Fix: The 45-Second Solution

Corrupted Ngc container files, stale Web Account Manager (WAM) tokens, or TPM crypto-key desynchronization cause Windows Hello passwordless sign-in failures in Microsoft 365 apps. Risk Tier: Low to Moderate (blocks biometrics/PIN; password fallbacks work). Primary Reset Step: Clear stale credentials in Windows Credential Manager and rename the %SystemRoot%\ServiceProfiles\LocalService\AppData\Local\Microsoft\Ngc folder after stopping the Key Isolation service.

Diagnostic Snapshot

• Severity Tier: Moderate (disrupts passwordless single sign-on across Microsoft 365 apps and forces repeated credential prompts).
• Data Safety Risk: Zero (local files, emails, and cloud data remain entirely safe on disk and online).
• Common Cause: Corrupted local Ngc key container, stale WAM identity tokens, or TPM attestation desynchronization.
• Admin Requirement: Local Administrator privileges required to clear system-level Ngc folders and reset biometric container services.

The System Break (What This Means)

Windows Hello for Business relies on a two-part cryptographic key pair to provide passwordless single sign-on. The private key is sealed inside your device’s physical Trusted Platform Module (TPM) chip and protected by your PIN or biometric data inside a local folder called the Ngc container. The public key resides in Microsoft Entra ID. When you launch an app like Outlook, the Web Account Manager (WAM) requests a signature from the TPM to prove your identity.

If a Windows update, BIOS flash, or abrupt shutdown corrupts the files inside the Ngc container, or if the TPM key cache desynchronizes from Entra ID, the cryptographic handshake fails. Think of it like a bank vault with a biometric lock and a matching keycard. If the lock’s internal memory board gets wiped during a power spike, presenting your valid fingerprint or keycard won’t open the door because the lock can no longer read its own saved key patterns.

Conflict Escalators

• Motherboard BIOS or TPM Firmware Updates: Updating motherboard firmware often clears or resets the TPM chip’s security state, invalidating saved Windows Hello private keys.
• Fast Startup Enabled: Windows Fast Startup caches kernel identity states across reboots, preventing stale WAM tokens from flushing out during standard shutdowns.
• Windows 11 Feature Updates: Major OS updates can modify permission access ACLs on the LocalService AppData folders, blocking the Key Isolation service from reading Ngc keys.

Common Misdiagnoses

• Misdiagnosing as an Expired Password: Users assume their domain or account password expired. However, entering a password works fine; the failure is strictly in the local Windows Hello biometric/PIN cryptographic broker.
• Misdiagnosing as an Office Licensing Defect: Reinstalling or repairing Microsoft 365 Apps does not solve Windows Hello failures because the issue resides within the Windows OS identity layers and TPM hardware state.

Immediate Action Steps

Step 1: Clear the Local Ngc Key Container

1. Open Command Prompt as Administrator.
2. Stop the CNG Key Isolation service:DOS net stop KeyIso
3. Open File Explorer and navigate to:
   C:\Windows\ServiceProfiles\LocalService\AppData\Local\Microsoft(Enable “Hidden items” under the View tab if folders do not appear).
4. Take ownership of the Ngc folder:DOS takeown /f C:\Windows\ServiceProfiles\LocalService\AppData\Local\Microsoft\Ngc /r /d y icacls C:\Windows\ServiceProfiles\LocalService\AppData\Local\Microsoft\Ngc /grant administrators:F /t
5. Delete all contents inside the Ngc folder (or rename the folder to Ngc.old).
6. Restart the CNG Key Isolation service:DOS net start KeyIso

Step 2: Clear BrokerPlugin Cache and Stale WAM Tokens

1. Close all Microsoft 365 apps.
2. Press Win + R, paste the following path, and press Enter:
   %LocalAppData%\Packages\Microsoft.AAD.BrokerPlugin_cw5n1h2txyewy\AC\TokenBroker\Accounts
3. Select all files in this folder and delete them.
4. Open Control Panel > Credential Manager > Windows Credentials.
5. Remove all entries starting with adal_, MicrosoftOffice16_Data:, or WindowsHello:.

Step 3: Re-register Windows Hello PIN and Biometrics

1. Open Settings > Accounts > Sign-in options.
2. Select PIN (Windows Hello) and click Remove.
3. Confirm PIN removal by entering your account password.
4. Click Set up under PIN (Windows Hello) and create a new PIN.
5. Re-configure Facial Recognition or Fingerprint biometrics if applicable.
6. Restart the computer and launch Word or Outlook to test passwordless authentication.

Hard-Stop Red Flags

• TPM Hardware Error 80090016: System logs display 0x80090016 or NTE_BAD_KEYSET, indicating physical TPM chip corruption or missing hardware keys.
• Account Disabled in Entra ID: Error displays 135011 or “Your organization has disabled this device.”
• Intune Compliance Lockout: Access blocked by conditional access requiring an updated device health attestation.

What the IT Admin Will Check

• Entra ID Sign-in and Audit Logs: Verify if Windows Hello for Business authentication attempts show Success or Failure under authentication details.
• Intune Windows Hello for Business Policy: Confirm that “Use Windows Hello for Business” is enabled and key trust models (Key Trust vs. Cert Trust) match the tenant setup.
• TPM Attestation and Device Registration: Run dsregcmd /status in Command Prompt to verify NgcSet : YES and ensure AzureAdPrt : YES.

Resolution Complexity

• Complexity Level: Moderate.
• Resolution Scope: Local device fix taking 10 to 15 minutes by rebuilding the Ngc folder and clearing cached WAM tokens. IT Admin intervention required only for TPM clear procedures or Entra ID re-registration.

Ticket Closed

When Windows Hello passwordless authentication fails in Microsoft 365, deleting the contents of the local Ngc container folder and clearing cached BrokerPlugin tokens resets the cryptographic key state. Re-enabling Windows Hello under Account Settings establishes a clean key pair with Microsoft Entra ID, restoring seamless single sign-on.