The Hybrid Admin

If you are staring at Error 0xCAA20003, you’ve hit a wall in the “Handshake” phase. While other errors might mean the server is down or your password is wrong, this specific code usually means your request reached the server, but the server didn’t like the way you asked. It’s a “Handshake Failed” error, often caused by a date/time mismatch or a conflict in the cached credentials stored in your Windows Vault.

Here is how to unblock the authorization and get back into your meetings.

Step 1: The “Time Traveler” Fix

It sounds simple, but 0xCAA20003 is frequently caused by your computer’s clock being out of sync with the Microsoft Entra ID servers. If your system time is off by even a couple of minutes, the security certificate is viewed as invalid, and authorization is blocked.

1. Right-click the Date and Time in your taskbar and select Adjust date and time.
2. Toggle Set time automatically to Off, then back to On.
3. Click the Sync now button under “Synchronize your clock.”
4. Restart Teams and try to sign in.

Step 2: Clear the Windows Credential Manager

Sometimes Windows saves a “bad” version of your token in its internal vault. Teams keeps trying to use this broken key instead of asking for a new one.

1. Type Credential Manager in the Windows search bar and open it.
2. Select Windows Credentials.
3. Look for any entries containing MicrosoftAccount:user=, msteams, or Microsoft_admed.
4. Click the drop-down arrow next to these entries and select Remove.
5. Restart Teams. It will now force a fresh login prompt, creating a clean authorization token.

Step 3: Re-Register the Microsoft.AAD.BrokerPlugin

Since this is an authorization error, the background process that handles “Work or School” logins might be unresponsive. You can “kickstart” it using a quick command.

1. Right-click the Start button and select Terminal (Admin) or PowerShell (Admin).
2. Copy and paste the following command:if (-not (Get-AppxPackage Microsoft.AAD.BrokerPlugin)) { Add-AppxPackage -Register "$Env:SystemRoot\SystemApps\Microsoft.AAD.BrokerPlugin_cw5n1h2txyewy\AppxManifest.xml" -DisableDevelopmentMode -ForceApplicationShutdown }
3. Press Enter, then restart your PC.

Step 4: Check for Multiple Signed-in Accounts

If you use a personal Microsoft account and a work account on the same machine, Windows “Account Bridge” can get confused about which one is trying to authorize.

1. Go to Settings > Accounts > Email & accounts.
2. If you see your work email listed twice or a personal email that you don’t use for Teams, click it and select Manage, then sign out.
3. Try signing into the Teams app again using only the primary work credential.

Quick Reference: 0xCAA20003 Fixes

Potential Cause	The Fix
Clock Desync	Click “Sync Now” in Date & Time Settings.
Old Vault Tokens	Remove msteams entries from Credential Manager.
Account Conflict	Remove unused accounts from “Email & accounts” settings.
Auth Plugin Stalled	Re-register the BrokerPlugin via PowerShell.