Office Activation Errors

How to Fix Microsoft 365 Activation Error Code 29 After Payment

Muhammad Talha Sep 28, 2026 870 views

Question details

The user is unable to activate Microsoft 365 and continuously encounters error code 29, even after successfully paying for a late subscription and re-signing into the application.

How to Fix Microsoft 365 Activation Error Code 29 After Payment

Product: Microsoft 365
Device & OS: not provided
Scenario: Attempting to activate Microsoft 365 after renewing a late subscription payment.
Observed behavior: Microsoft 365 displays error code 29 and remains unactivated despite a successful payment and standard sign-out/sign-in attempts.

Before you start

Verify that your Microsoft 365 subscription shows as 'Active' in your Microsoft account dashboard and that you are using the correct login credentials. It is strongly recommended to back up your Office files and create a Windows System Restore point before proceeding with advanced cache or registry modifications.

Solution 1Recommended

Clear Office Authentication Cache Folders

Removing the corrupted OneAuth and IdentityCache folders forces Microsoft 365 to rebuild your activation profile, which often resolves error code 29.

When a subscription is renewed late, the local authentication cache on your device may fail to sync with Microsoft's servers, retaining the expired status.

Close all Office applications

Ensure that Word, Excel, PowerPoint, and any other Microsoft 365 applications are completely closed.

Navigate to the Office AppData folder

Press the Windows Key + R to open the Run dialog. Type %localappdata%\Microsoft\Office\16.0 and press Enter.

Delete authentication folders

Locate the folders named 'OneAuth' and 'IdentityCache'. Right-click each folder and select Delete.

Restart and sign in

Restart your computer, open any Microsoft 365 application, and sign in again with your Microsoft account credentials to activate the software.

Clear Office Authentication Cache Folders

Data Safety: Deleting these cache folders is perfectly safe and will not delete any of your personal documents or spreadsheets.

Solution 2

Delete the Office Identity Registry Key

If clearing the local cache folders does not work, removing the Identity registry key can force a deep reset of your Microsoft 365 license recognition.

Solution 3

Reinstall Microsoft 365 via Offline Installer

Using an offline installer bypasses potential network cache issues and installs a fresh, uncorrupted version of Microsoft 365.

Free Microsoft Office alternative

Switch to WPS Office to Avoid Activation Errors

Tired of dealing with subscription renewals, late payment lockouts, and frustrating issues like Microsoft 365 activation error code 29? WPS Office provides a powerful, free, and lightweight alternative to Microsoft Office, allowing you to focus on your work without complex activation hurdles.

1. Download the installer: Visit the official WPS website and click the free download button for your operating system.
2. Install WPS Office: Run the setup file and follow the quick installation prompts to set up the software in minutes.
3. Open your Microsoft files directly: Launch WPS Office and immediately open, edit, and save your existing Word, Excel, and PowerPoint documents without any conversion.

Bypass frustrating Microsoft 365 subscription activation errors and late-payment lockouts entirely.Fully compatible with Microsoft Word, Excel, and PowerPoint formats (.docx, .xlsx, .pptx) for seamless file sharing.Completely free to use with an intuitive interface that requires zero learning curve for former Microsoft Office users.Lightweight design that installs quickly and consumes minimal system resources.

Frequently Asked Questions

Why do I get Microsoft 365 error code 29 after successfully paying my late subscription?

This error occurs because the local authentication cache files on your computer fail to synchronize with Microsoft's servers. Your local software still believes the subscription is expired, even though the payment was processed on the server end.

Will I lose my files if I delete the OneAuth and IdentityCache folders?

No. The OneAuth and IdentityCache folders only contain login and license authentication data. Deleting them will not affect your Word documents, Excel spreadsheets, or any other personal files.

What should I do if clearing the cache and modifying the registry doesn't fix error 29?

If advanced troubleshooting does not resolve the issue, you should use the Microsoft Support and Recovery Assistant (SaRA) tool to completely wipe Office from your system, or consider installing Microsoft 365 using the official Offline Installer.

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