Have you encountered the confusing “Class not registered” error in Windows 11? You are not alone. This message may suddenly appear when you try to open a standard application, such as Photos or Calculator, or even the Start menu. The error sounds scary, but in reality, it's often caused by a minor glitch in system files or registry settings.
Most often, the culprit is the database where Windows stores information about all installed programs and components. Sometimes its entries become corrupted, and the system simply “forgets” how to open the desired application. As a result, you see this message about an unregistered class.
The good news is that in most cases, you can fix the problem yourself in a few minutes. You don't need to be a computer genius. Simple built-in Windows tools, such as PowerShell or the troubleshooter, can automatically find and fix corrupted entries, returning everything to working order.
Determining the type of error
Before looking for a solution to the “Class not registered” error, you should determine what it may be related to, as there are several possible causes and, accordingly, different solutions. Most often, the problem is noticed in the following circumstances:
- trying to launch a web browser;
- viewing image files;
- using standard OS applications;
- opening standard “Settings” button or clicking on the Start.
If you are experiencing one (or more) of the above situations, then look for a solution below in the relevant section of the article. Possible fixes are presented here in more detail.
Option 1: Browser
If a warning that the class is not registered appears when you try to launch the web browser, set the default application for opening certain files:
- Click on the button “Start” and go to ‘Settings’.
- On the left panel, select the tab “Apps”, then open the section “Default apps”.
- Find the problematic browser in the list of software and click on the line with its name.
- In the next window, click on “Default”, to make the browser the application in which all links will be opened.
- Below, you should also set associations by file type. Select a browser for all types where possible by clicking on the line with the extension, then specifying the desired application.
After that, you can close the window with file associations ‘Settings’ and try restarting your browser.
If the instructions do not work, you can always reinstall the browser, which is especially easy with the synchronization feature enabled (all bookmarks, passwords, and data will also be available again after logging into the corresponding account in the browser). We have written in more detail about how to reinstall the most popular applications in a separate article.
More details: How to reinstall Google Chrome / Yandex Browser / Opera
The “Class not registered” error in Windows 11 usually appears when the system cannot find the necessary settings to launch a program or component. Most often, this is due to damaged or missing registry entries, problems with system updates, or application malfunctions. You can fix it by restarting the problematic program as an administrator, restoring system files using built-in Windows tools, or re-registering the necessary components via the command line. In most cases, the solution is simple and does not require any special knowledge.
Option 2: View images
In the case of applications that are tools for viewing images, you need to proceed in much the same way as in the previous option with browsers. First, set the file associations:
- In the list of software in the section “Default apps” (Steps 1 and 2 from the instructions above) find the program that causes the error when launched. Let's look at the algorithm of actions using the example of the pre-installed application “Photos”.
- Set this application to open file types by clicking on the extension name and selecting the desired option.
“DXSETUP”
- To do this, return to the tab “Applications” standard App access to file system – access to the file system;, then select “Installed applications”.
- App access to microphone – access to the microphone; “Additional parameters”.
- Go down to the block “Reset” and click on the button “Reset”.
All that remains is to confirm the action and try to run the application or file that it should open again.
Key points “Advanced Options” may not be the case with third-party applications, so it will not be possible to reset the status of such software using built-in tools. Instead, the software will need to be reinstalled.
Option 3: Standard applications
If this problem occurs with standard applications, you may also need to reinstall the software after uninstalling it first. In the section with installed system applications “Settings” find the problematic program, click on the three dots and select the removal option. Most often, the uninstallation wizard will start, and you will need to follow the instructions to clean up.
To be sure to delete all residual files and data in the cache that may remain after uninstallation, you can use specialized software. We analyzed the algorithm of actions using the example of the most popular products.
More details: How to use CCleaner / Revo Uninstaller
Unfortunately, system applications are not so easy to remove, since standard methods (the section with applications “Settings” or “Control Panel” do not provide this option. But even in this case, there are solutions – the Windows 11 console or specialized utilities, which we wrote about earlier.
More info: Removing built-in apps in Windows 11
Option 4: Start button or taskbar
If when you try to press the button “Start” or open “Settings” if this problem occurs, there are several ways to fix it.
Method 1: Re-register system files
First, try re-registering some of the system file libraries that are responsible for the taskbar.
- Since almost all methods involve opening the console, and it is launched from the main menu, which may not work, as an alternative, you need to go to “Task Manager” — simultaneously press the keys “Ctrl + Shift + Esc”.
- Then, in the window that opens, click on “Start a new task”.
- Enter in the field
PowerShell, check the option “Create task with administrator rights” and click on the button “OK”. 
- Next, you can proceed to the actual re-registration of files. To do this, paste the following commands into the command console window, executing them all at once by pressing the “Enter”:
regsvr32 quartz.dll
regsvr32 qdv.dll
regsvr32 wmpasf.dll
regsvr32 acelpdec.ax
regsvr32 qcap.dll
regsvr32 psisrndr.ax
regsvr32 qdvd.dll
regsvr32 g711codc.ax
regsvr32 iac25_32.ax
regsvr32 ir50_32.dll
regsvr32 ivfsrc.ax
regsvr32 msscds32.ax
try using another command that reinstalls the pre-installed Microsoft Store application — this may help solve the problem.
regsvr32 mpg2splt.ax
regsvr32 mpeg2data.ax
regsvr32 sbe.dll
regsvr32 qedit.dll
regsvr32 wmmfilt.dll
regsvr32 vbisurf.ax
regsvr32 wiasf.ax
regsvr32 msadds.ax
regsvr32 wmv8ds32.ax
regsvr32 wmvds32.ax
regsvr32 qasf.dll
regsvr32 wstdecod.dll 
You can also execute these commands one at a time by pressing the Enter key after each one. It should be noted that in addition to windows with a message about successful re-registration, windows with errors may also appear – this is normal, just close them. If you are applying the commands one at a time, then after an unsuccessful re-registration attempt, move on to the next one.
Once all files have been re-registered, restart your computer (this can also be done via the console) and check if the taskbar has started responding to interaction attempts.
Method 2: Console command
Try using another command that reinstalls the pre-installed Microsoft Store app—this may help resolve the issue.
Do the same as in the previous instructions (Steps 1-3) to open “Windows PowerShell”, then enter the command Get-AppXPackage -AllUsers | Foreach {Add-AppxPackage -DisableDevelopmentMode -Register “$($_.InstallLocation)\AppXManifest.xml”} and run it by pressing the “Enter”.
After completing the request, restart your computer and check that everything is working properly. “Start” and the taskbar.
Method 3: Checking the system for errors
If nothing has helped to resolve the taskbar issue, then you can check the entire system for errors. The methods described in our separate article on this topic at the link below will not only fix the warning that the class is not registered, but also other issues. The procedure is performed using built-in system tools and specialized software.
Read more: Ways to check Windows 11 for errors
We also recommend reading our article describing the most common problems with the button “Start” in Windows 11 and methods for solving them. Most of the options will help in your situation to one degree or another.
More details: Solving problems with opening the Start menu in Windows 11
As you can see, the “Class not registered” error in Windows 11 is an unpleasant but often solvable problem. It does not mean that something is seriously wrong with your computer. Most often, the problem is caused by a malfunction in the app store or system components that are responsible for the correct launch of programs.
The suggested solutions, from a simple reboot to using built-in utilities to check system files, will help you restore everything to working order step by step. Always start with the simplest methods; in most cases, they work.
The main thing is not to be afraid to try. These instructions are safe and will not harm your system. If one option does not help, just move on to the next one. Most likely, you will find a suitable solution and be able to continue working without any hassle.
