Microsoft 365 Error Codes

How to Fix Office 2021 Error 0xC0000142 After Windows 11 Restart

Algirdas Jasaitis Oct 10, 2026 868 views

Question details

User needs to permanently resolve Office 2021 Error 0xC0000142, which continuously appears when opening Excel or other Office applications after restarting Windows 11.

How to Fix Office 2021 Error 0xC0000142 After Windows Restarts

Product: Microsoft Office 2021
Device & OS: Windows 11
Scenario: Opening Office 2021 applications like Excel after a system restart.
Observed behavior: Office applications fail to launch, displaying error code 0xC0000142. Standard repairs, generic reinstallations, and updates do not provide a permanent fix.

Before you start

Ensure you have completely backed up all important personal files and documents to an external drive or cloud storage, as fixing persistent system-level application errors may require a full Windows reset.

Solution 1Recommended

Perform a Clean Reinstallation Using the Office Removal Tool

Use the official Microsoft Support and Recovery Assistant to completely eradicate corrupted preinstalled trials and faulty Office configurations before reinstalling.

Standard uninstallation often leaves behind corrupted registry keys or temporary files that cause Error 0xC0000142 to persist. Using the official removal tool ensures a clean slate.

Uninstall Preinstalled Trials

Go to Windows Settings > Apps > Installed apps and remove any preinstalled Microsoft Office 365 trial versions.

Run the Removal Tool

Download and run the Microsoft Support and Recovery Assistant to completely wipe all remaining Office 2021 files from your system.

Restart Windows

Reboot your computer to ensure all background registry keys and temporary files are fully cleared from memory.

Reinstall Office 2021

Log into your Microsoft account online, download your specific Office 2021 installer, and follow the setup prompts to complete a fresh installation.

Perform a Clean Reinstallation Using the Office Removal Tool

Clean Installation: Removing the preinstalled trial before installing your purchased version prevents licensing and file conflicts.

Solution 2

Reset Windows 11 via Advanced Startup

If standard uninstallation fails or the operating system update stalls, use Advanced Startup to reset Windows and eliminate deeper OS or third-party software interference.

Free Microsoft Office alternative

Avoid Persistent Installation Errors with WPS Office

Struggling with complex Office 2021 installation errors and forced Windows resets? Switch to WPS Office. It is a lightweight, reliable, and completely free alternative that seamlessly handles all your Word, Excel, and PowerPoint files without the heavy system requirements or frustrating crash loops.

1. Download the Installer: Visit the official WPS Office website and click the download button for the free Windows version.
2. Install Quickly: Run the lightweight installer to set up the software in minutes without complicated system changes.
3. Open Your Files: Double-click your existing Microsoft Office documents to instantly open and edit them in WPS Office.

Highly compatible with Microsoft Office formats including .docx, .xlsx, and .pptxLightweight installation that avoids deep Windows registry conflictsFamiliar user interface requiring zero learning curveFree to use with powerful built-in PDF editing tools

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Frequently Asked Questions

What causes error code 0xC0000142 in Microsoft Office?

Error 0xC0000142 typically indicates an application initialization failure. In Office 2021, this is often caused by corrupted installation files, conflicting third-party background software, or remnants of a preinstalled Office 365 trial version.

Will the Microsoft Office removal tool delete my personal documents?

No, the Microsoft Support and Recovery Assistant only removes the Office application files, registry keys, and software settings. Your personal Word documents, Excel spreadsheets, and PowerPoint presentations remain safe on your hard drive.

How do I find out which application is conflicting with Office?

After performing a clean installation of Windows and Office, install your third-party applications one at a time. Restart your PC and open an Office app like Excel after each installation to isolate which specific software triggers the error.

Microsoft Office Error Codes