How to Fix the “Class Not Registered” Error (0x80040154) in Windows 11 For today’s video, we’ll be discussing the “Class not registered” error, also known as 0x80040154, in Windows 10 and 11. This error usually appears when a system component, app, or DLL isn’t properly registered. In this walkthrough, we’ll show you how to fix the “class not registered” error in Windows 11. Before we begin, be sure to subscribe to NinjaOne's IT Video Hub and our YouTube channel for more tech content like this. Prerequisites Before we start, make sure you have administrator access and that your system is fully updated with the latest windows patches. You can also use Event Viewer to identify what's triggering the error. Check the Application logs for entries marked with Event ID 0x80040154 and take note of the faulty module or CLSID to identify the source of the problem. Check out our blog for more information. How to Fix the “Class Not Registered” Error (0x80040154) Some of the methods outlined below require a basic familiarity with scripting. For these methods, the full instructions and scripts will be on the blog. Method 1: Settings The most common cause of this error is a missing or corrupted COM or DLL registration. Re-registering the affected component usually resolves it. For DLLs: Open Command Prompt as administrator and run regsvr32 followed by the path to the DLL. Here's an example: regsvr32 ExplorerFrame.dll For Microsoft Store apps: Use PowerShell with a re-registration script to repair apps like Photos, Calculator, or Edge without deleting user data. Our blog has the re-registration script in full. Method 2: System File Checker (SFC) If the problem is deeper in your system files, use SFC. This is your first line of defense against corrupted system files. Open Command Prompt as administrator and run sfc /scannow, then let the scan finish. If issues are repaired, restart your PC. If not, move on to the next method. Method 3: Deployment Image Servicing and Management (DISM) Tool If SFC can’t fix everything, the Deployment Image Servicing and Management tool—or DISM— can restore the system image. It repairs the Windows Component Store, which SFC relies on to replace corrupted files. Again, open Command Prompt as an administrator and run: DISM /Online /Cleanup-Image /RestoreHealth After the scan is done, restart and rerun the sfc /scannow command. Method 4: Reset or Reinstall Apps Sometimes the error is tied to a built-in app like Photos or Calculator. This method restores missing COM registrations and app dependencies. Go to Settings > Apps > Installed apps. Find the app, open Advanced options, and select Repair. If that fails, try Reset. If neither works, uninstall and reinstall the app using PowerShell. Check our blog for the full script. In summary, you can fix the “Class not registered” error by re-registering components, repairing system files, moving to SFC and DISM for system-level fixes, and resetting or reinstalling apps if needed. For more information, check out our official blog post on how to fix the “Class Not Registered” error (0x80040154) in Windows 11, linked in the description below.