Microsoft 365 Error Codes

How to Fix Microsoft Error Code 3399811147 and Error 7ita9

Phi Hung Vo Sep 29, 2026 868 views

Question details

The user needs to resolve Microsoft error code 3399811147 and correlation error 7ita9, which prevent successful sign-in or application launch.

How to Troubleshoot Microsoft Error Code 3399811147 and Error 7ita9

Product: Microsoft 365
Device & OS: Windows
Scenario: Attempting to sign in to a Microsoft account or launching a Microsoft 365 application like Outlook.
Observed behavior: The application fails to load or authenticate, returning an unexpected problem prompt with error code 3399811147 and error 7ita9.

Before you start

Ensure you have administrator privileges on your Windows computer and close all running Microsoft applications, such as Outlook, Word, and Excel, before proceeding.

Solution 1Recommended

Re-register the Microsoft AAD Broker Plugin

Use this solution to repair the Azure Active Directory (AAD) Broker Plugin, which is often responsible for handling Microsoft sign-in prompts and authentication tokens.

The Microsoft AAD Broker Plugin can sometimes become unregistered or corrupted following a system update or application crash. Re-registering it via Windows Terminal forces Windows to recognize and repair the authentication module.

Open Windows Terminal as Administrator

Right-click the Windows Start menu button and select 'Windows Terminal (Admin)' or 'Windows PowerShell (Admin)' from the context menu.

Run the Re-register Command

Copy and paste the following command into the terminal, then press Enter: if (-not (Get-AppxPackage Microsoft.AAD.BrokerPlugin)) { Add-AppxPackage -Register "$env:windir\SystemApps\Microsoft.AAD.BrokerPlugin_cw5n1h2txyewy\Appxmanifest.xml" -DisableDevelopmentMode -ForceApplicationShutdown }

Restart Your Computer

Once the command executes successfully, restart Windows and try signing into your Microsoft application again.

Re-register the Microsoft AAD Broker Plugin

Command Execution: If the command returns no text and drops you to a new prompt line, it has executed successfully.

Solution 2

Clear the Windows Credential Manager

Removing corrupted or outdated Microsoft account credentials from the system can force the application to generate a fresh, error-free sign-in token.

Solution 3

Clear the IdentityCache and OneAuth Folders

Manually deleting cached identity files can resolve persistent error 7ita9 issues caused by corrupted local application data.

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1. Download the Installer: Visit the official WPS Office website and download the free installation package for your operating system.
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Frequently Asked Questions

What does Microsoft error code 3399811147 mean?

Error code 3399811147, often accompanied by error 7ita9, indicates that a Microsoft 365 application encountered an unexpected problem during the authentication process. It is typically caused by a corrupted Azure Active Directory (AAD) Broker Plugin or corrupted local identity cache.

Will clearing the Credential Manager delete my files?

No. The Windows Credential Manager only stores your saved passwords and authentication tokens. Removing entries will simply require you to sign in again the next time you open a Microsoft application, and it will not affect your personal documents or emails.

How do I access Windows Terminal as an administrator?

You can access it by right-clicking the Start button on your Windows taskbar and selecting 'Windows Terminal (Admin)' or 'Windows PowerShell (Admin)' from the menu. You must click 'Yes' on the User Account Control prompt to grant it administrative privileges.

What should I do if re-registering the AAD Broker Plugin doesn't work?

If the PowerShell command does not resolve the issue, proceed to clear your Windows Credential Manager entries and delete the contents of your IdentityCache and OneAuth folders in the local AppData directory. If all local troubleshooting fails, you may need to contact Microsoft Support with your specific correlation ID.

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