Windows Defender usually receives occasional definition updates automatically on your Windows 10 or Windows 11. As this downloading and installation process happens completely in the background, you don’t need to pay attention to it. But sometimes you may see ‘Windows Update won’t update‘ error message has appeared in the Setting menu. Follow these easy solutions to fix the issue at ease.
Fix 1 – Automate some services
Some services are essential for WU service.
1. Type “cmd” in the search box.
2. Next, right-click on “Command Prompt“. To access the Command Prompt as an administrator, click on the “Run as administrator“.
3. After that, write this code and then hit Enter to execute it on your computer.
sc config wuauserv start=auto sc config bits start=auto sc config cryptsvc start=auto sc config trustedinstaller start=auto
Once you have automated these four services close the CMD terminal and restart your computer.
Fix 2 – Rename particular folders
Renaming a particular folder may help you solve this problem.
1. At first, you need to type “cmd” from the search box.
2. After that, right-click on “Command Prompt” and choose “Run as administrator“.
3. To stall some services, execute these four commands. Copy-paste and hit Enter to execute them all.
net stop wuauserv net stop cryptSvc net stop bits net stop msiserver
4. For the main step, you need to rename two important files. To do so, run these two commands in the CMD window.
ren C:\Windows\SoftwareDistribution SoftwareDistribution.old
ren C:\Windows\System32\catroot2 catroot2.old
5. For the final step you need to resume those stalled services. To do so run these 4 codes sequentially.
net start wuauserv net start cryptSvc net start bits net start msiserver
Close the Command Prompt window.
6. Now, press the Windows key along with the ‘X‘ key.
7. Then, click on the “Windows PowerShell (Admin)” to access the PowerShell.
8. When you have the access to the PowerShell terminal, run this command by typing it and hitting Enter afterward.
Restart your computer to finalize this process.
Fix 3 – Windows Update troubleshooter
If this problem is happening due to the Windows Update issue, this should help to solve the issue.
1. Just type “Troubleshoot setting”
2. Then you need to click on the “Troubleshoot setting“.
2. When the Settings window appears, click on the “Additional troubleshooters” to see additional troubleshooting options.
3. Then, click on “Windows Update” troubleshooter, followed by another click on “Run the troubleshooter“.
4. Follow the instructions that appear on your screen.
5. Once you are finished troubleshooting your issues, click on “Close the troubleshooter“.
Restart your computer, if required.
This should fix the issue you are facing.
Fix 4 – Empty SoftwareDistribution folder
1- Just Press The shift key on your Keyboard and keeping it pressed click on restart to restart PC.
2. Once your pc reboots into the Windows RE, you have to click on “Troubleshoot“.
6. After that, choose the “Advanced options” menu.
7. Simply, click on the “Startup Settings“.
8.Finally to restart your device in the correct manner, click on “Restart“.
9. Here you will detect various possibilities of startup types.
10. Then, press F4 from your keyboard to select the option that says “Enable Safe Mode“.
Soon, your computer will boot into safe mode.
10. Press Windows key+R to launch Run.
11. To access the Download folder, paste this location, and hit Enter.
12. Once you reach the SoftwareDistribution folder, remove everything from it.
Close File Explorer window.
Reboot your computer. It will be booted normally.
Check if it is happening or not.
Fix 5 – Try updating Windows Defender manually
If the automated update is failing, you can manually update it.
1. At first, you need to search for “Windows security“.
2. Then click on the “Windows Security“.
3. Once you are in the Windows Security, click on the “Virus & threat protection” settings.
4. Scroll down and in the ‘Virus & threat protection updates’ section, click on the “Check for updates“.
5. In the Protection updates window, click on “Check for updates“.
Now simply need to wait for this update process to finish.
Fix 6 – Use a batch file to fix this issue
You need to create a new batch file and run it on your device to fix the Windows Defender related issue.
1. Type “Notepad” in the search box.
2. Click on “Notepad” in the elevated search results.
3. Once the blank Notepad appears on your screen, copy-paste this code.
cd %ProgramFiles%\Windows Defender MpCmdRun.exe -removedefinitions -dynamicsignatures MpCmdRun.exe -SignatureUpdate
4. After that, click on the “File” and then on “Save As…”
5. Now, set the ‘Save as type:’ to “All Files(*.*)“.
6. Set the name of the file as “defenderfix.bat“. Then, click on “Save“.
Once you have saved the file, close the Notepad.
7. Go to the location where you saved the ‘defenderfix.bat‘ batch file.
8. Right-click on the batch file and then click on “Run as administrator“.
This should fix the Windows Security issue on your computer.
Fix 7 – Download the definitions yourself
If nothing is working out for you, try downloading the definitions yourself.
1. Simply click on the below-mentioned link to start downloading the virus definitions.
2. Scroll down through the webpage until you see “Microsoft Defender Antivirus for Windows 10 and Windows 8.1“.
If you are on Windows 11 , then choose the version for windows 11
3. Then, click on appropriate architecture on the right next to it.
(Example- If your system is a ’64-bit’ system, you have to click on the “64-bit“)
4. As soon as you have clicked on that, choose a proper download location.
5. Click on “Save“.
Close the browser window.
Open the download location.
6. After that, double click on the “mpam-fe.exe” setup to run it.
Let it install the latest version of the Windows Security on your computer.
Fix 8 – Use WSUS offline installer
You can use WSUS offline installer to get Windows Security definition updates.
1. At first, go to the WSUS Offline Update.
2. Click on the “Download” section.
3. Then you have to click on the “Version” to start downloading it.
A zip file will be downloaded.
4. Go to the downloaded folder.
5. Extract that zip file on a location of your choice. Go to that location on your drive.
6. Now, double click on the “wsusoffline” folder to access it.
7. In the wsusoffline folder, double click on “UpdateGenerator.exe“.
8. Once the WSUS Offline Update opens up, uncheck everything in the ‘Windows 10 x86 versions’ and the ‘Windows 10 x64 versions’.
9. Now, check the “Include Windows Defender definitions“.
10. After that, click on “Start” to start the process.
A terminal window will appear detailing the on-going download processes.
You simply have to wait.
The definitions will be downloaded on your computer.
Close the WSUS Installer on your computer.
11. Coming back to the wsusoffline folder, double click on the “Client” folder.
12. Inside the ‘Client’ folder, you have to double click on the “UpdateInstaller.exe“.
13. In the WSUS Offline Updater, check the option that you want to install on your computer.
14. After that, click on “Start” to start.
This way you can fix the problem of Windows Defender.
Sambit is a Mechanical Engineer By qualification who loves to write about Windows 10 and solutions to weirdest possible problems.