Windows 10 update failed to install error code 0xc000021a

Hey Windows enthusiasts! Today, let’s dive into the intriguing world of Windows 10 updates, specifically tackling the pesky issue that leaves many users scratching their heads: the notorious Error Code 0xc000021a. I recently found myself wrestling with this digital dilemma, and after some trial and error, I’m here to share my experiences and hopefully help you bid farewell to this update hiccup.

The Frustrating Encounter

Imagine this: you’re eagerly waiting for your Windows 10 update to install, and just when you think it’s smooth sailing, bam! Error Code 0xc000021a rears its ugly head. Frustration, confusion, and a hint of panic set in – been there, done that.

Windows 10 update failed to install error code 0xc000021a

Understanding the Culprit

Before we delve into solutions, let’s demystify the error a bit. Error Code 0xc000021a typically occurs when there’s a critical system process failure. It’s like a digital roadblock preventing your update from seamlessly installing. But fear not, for where there’s a will, there’s a Windows way.

Fix #1: Update Windows Manually

I kicked off my troubleshooting journey by attempting a manual update. Sometimes, the automated process falters, and lending a helping hand can work wonders. Head over to the Windows Update settings, click “Check for updates,” and let Windows do its thing. For a step-by-step guide, check out this informative article from Microsoft’s support page.

Fix #2: Unleash the SFC Scanner

In my quest for a resolution, I stumbled upon the System File Checker (SFC) tool. This nifty command-line utility scans and repairs corrupted system files. Open Command Prompt as an administrator, type ‘sfc /scannow,’ and let the magic unfold. For a detailed walkthrough, this tutorial [insert link] proved invaluable.

Fix #3: Embrace the DISM Command

Another potent weapon in my troubleshooting arsenal was the Deployment Image Service and Management Tool (DISM). Executing ‘DISM /Online /Cleanup-Image /Restore Health’ in Command Prompt acted as a digital medic, repairing underlying issues. Remember to reboot your system afterward to solidify the fixes.


Facing the Error Code 0xc000021a is undoubtedly a Windows user’s rite of passage. However, armed with the right knowledge and a dash of patience, you can triumph over this update obstacle.

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Benjamin Johnson

Hey there, I'm Ben, the tech-savvy Founder and CEO of I've dedicated my life to helping fellow Windows users optimize their PCs for peak performance. Join me on this journey as we unlock the full potential of your Windows devices together!

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