Microsoft provides updates for Windows and its components quite frequently. However, while updates are generally helpful for system performance and fixing bugs, users often encounter issues when they download them.
There are plenty of fixes to try when the system updates fail, but what should you do when a program update fails? Throughout this guide, we’ll explore some solutions to try when the Microsoft Defender update won’t work, a common problem faced by both Windows 10 and 11 users. Proceed with the method that fits your situation the best.
Understanding the Causes Behind a Failed Microsoft Defender Update
Before you jump straight into troubleshooting, it’s important to understand what may be causing the issue in your case. We did a bit of research and discovered that one or more of the following can be contributing to the Microsoft Defender update problem:
- The update components required by Windows to install the system and app updates are not functioning properly. They can either be corrupt or broken, which leads to the issue at hand.
- A third-party antivirus solution installed on your computer is interfering with Defender updates, stopping them midway or preventing them from even starting.
- The system itself is dealing with some kind of corruption error or inconsistency. When this happens, you are likely to face one or more issues while performing routine operations.
Now that you know what might be causing the issue, it is time we get started with the troubleshooting methods that can help fix the problem in no time.
1. Disable Any Third-Party Antivirus Programs
It is not uncommon for third-party antivirus programs to interfere with the processes of Microsoft Defender, especially in situations like the one at hand.
The only effective solution, in this case, is to disable all the third-party security programs and then try to install the Defender updates again. Once the updates are successfully installed, you can enable the security programs back.
To disable the security programs, you can simply right-click on their taskbar icon and choose Disable > Disable until the next restart. If you think that the antivirus solution is indeed the culprit, then we recommend you uninstall it and switch to one of the best third-party security solutions for Windows 10.
2. Reset the Windows Update Components
As we previously mentioned, you might also not be able to install Windows updates if the update components are corrupt or broken.
Since these components are essential for the update service to work, you must repair them in order to install the latest available updates. The best way to repair these components is by resetting them to their default state.
Here is how you can do that:
- Type cmd in Windows search and click on Run as administrator.
- Click Yes in the User Account Control prompt.
- In the following window, type the commands mentioned below one by one and hit Enter after each to execute it.
net stop wuauserv
net stop cryptSvc
net stop bits
net stop msiserver
- Once done, execute the following commands. This will restart the services you just disabled above.
net start wuauserv
net start cryptSvc
net start bits
net start msiserver
You can now close the Command Prompt window and check if the issue is resolved.
3. Restart the Microsoft Defender Service
There is also a chance that the issue is within the Microsoft Defender service itself. The service might be dealing with a temporary glitch or simply might be disabled.
In this method, we will be restarting the Microsoft Defender service and set its startup type as automatic. This way, the service will automatically launch when you boot into the system, allowing the system to install its updates without any problems.
Here is all that you need to do:
- Press Win + R to open Run.
- Type services.msc in Run and click Enter.
- In the following window, look for the Microsoft Defender Antivirus service and right-click on it.
- Choose Properties from the context menu.
- Now, click on the Stop button. Wait for a few moments before hitting Start.
- After the service is restarted, expand the dropdown for Startup type and choose Automatic.
- Click Apply > OK to save the changes.
- Once done, run SFC and DISM scans (see the difference between SFC, DISM, and CHKDSK for instructions) to rule out any corruption errors within the system which might be preventing Windows from installing the latest Defender update.
You can try reinstalling the targeted update after this is done and check if the issue is now fixed.
4. Manually Install the Targeted Update
Windows also provides you the option to install the pending updates manually if the automatic installation does not work.
We have a complete guide on how to install Microsoft Defender updates manually, and we recommend that you follow the steps mentioned there to install your targeted update.
For those who cannot install the update by following the instructions there, here is another method of installing the updates manually that worked for a few other users:
- Head over to the Microsoft Update catalog and search for the targeted update.
- Click on the Download button and wait for the process to complete.
- Save the downloaded files to a temp folder, and then run all the executable files.
- Once done, head over to the following location in File Explorer to find the platform version of Windows Security. Note down the platform version.
- Next, type cmd in Windows search and click on Run as administrator.
- Execute the following command. Make sure you replace the Platform number with the number you noted earlier.
cd C:\ProgramData\Microsoft\Windows Defender\Platform\platformnumber
- Now, execute the following:
C:\ProgramData\Microsoft\Windows Defender\Platform\platformnumber>MpCmdRun -SignatureUpdate
Once the command is executed, check if the update is successfully installed.
Update Microsoft Defender Successfully
Security tools such as Microsoft Defender keep your system safe from both internal and external threats. The program scans your system files and detects any potential problems that could expose your system to any type of risk. However, to function properly, it must be updated regularly, just like other system apps.
The methods listed above should have helped you install the latest Microsoft Defender updates. Whenever the problem appears again, we recommend you contact the official Microsoft support team so they can investigate the root cause of the problem and suggest a feasible solution accordingly.