Error code 0x800705b4 is an error that is related to Windows Defender, but is a rather generic error that doesn’t really give you too much details as to what the problem is.
There are two possible scenarios where you might be facing this issue. One of them is if you’re having issues with Windows Defender, such as it not running or crashing, and if that is the case, you will find your solution here. The other situation is if you’re having these issues with Windows Update, or more specifically, you can’t update your system, Windows Update hangs with an error message etc. This will prevent you from installing updates on your device, and some of them might be critical for multiple reasons, such as security or bug fixes, and installing them is important.
Fortunately, there are quite a few solutions that you can apply to solve this issue. Not all of them have been reported to work for everyone, and that is why there are so many of them. If one doesn’t work, feel free to move on and try the next one.
Method 1: Manually download the update
If Windows Update fails to update your device, you can take a look at the update number of the update that fails to install. You can then head to Microsoft’s Update Catalog and download the update that is causing you problems. After that, it’s as simple as opening your Downloads folder and double-clicking the setup file for the update. Make sure to reboot when it’s done. This is especially helpful with updates that are larger in size, such as the Anniversary Update.
Method 2: Run the Windows Update troubleshooter
Windows’ built-in troubleshooters are tools that tend to be stubborn, and there are certain situations where they simply won’t fix your problem, no matter what you do. This, however, is not such a case, as running the troubleshooter has helped more than one person having this issue.
- Press the Windows key on your keyboard and type in troubleshoot, then press Enter to open the result.
- On the left side, click on View All.
- From the list that opens, choose Windows Update near the bottom. Click Advanced in the next window, and then Next.
- Click Advanced, and then Run as an Administrator.
- Make sure that the Apply repairs automatically box is checked and click Next
- Click Close to finish troubleshooting, or if you want to see more details about the issues that may have been found and fixed, click View detailed information.
Method 3: Delete the SoftwareDistribution folder
Deleting this folder has become a method that helps with plenty of issues, due to the fact that it contains files that tend to get corrupted pretty easily, and then proceed to release mayhem on your device.
- Reboot your computer.
- Hold the Windows Key and Press X. Choose (Command Prompt) admin.
- Typenet stop bits
net stop wuauservCD %systemroot%\SoftwareDistributionRen Download Download.old
net start wuauserv
net start bits
- Now try updating Windows.
Method 4: Disable updates for other Microsoft products
Updates for other Microsoft products may actually be preventing you from downloading the critical updates for Windows. To fix this, you merely have to disable the feature until you have downloaded the critical updates, and you can re-enable it then.
- Press the Windows key on your keyboard, type in Check for updates and open the result.
- Under Update settings, click on Advanced options.
- Find the checkbox in front of Give me updates for other Microsoft products when I update Windows and make sure it is not checked.
- Reboot your device, and try running the updates again. They should complete successfully, but keep in mind that you may need to run the update multiple times to get all updates. You will know you’re good when you get the Your device is up to date
- You can now go to the Advanced options again, and re-enable updates for other Microsoft products. You should be able to continue with the regular updates now as well.
Method 5: Disable any third-party antivirus or firewall
Third-party antivirus or firewall software might be conflicting with the download of Windows Update, so you might want to disable them and see if you can download the updates now. Most of them can be disabled by right-clicking on their icon in the taskbar and choosing Disable.
Method 6: Make sure that the Windows Defender Service is started
As the error is often related to Windows Defender, you should check if the service is even running. If it isn’t, you should start it, that might fix your issues.
- Hold the Windows Key and Press X. Choose (Command Prompt) admin
- Typesc config “WinDefend” start= auto
Errors such as this one are among the main reasons why people had a tendency to stay away from Microsoft’s latest iteration of the Windows operating system. However, now, more than a year after its initial release, most of the problems have been fixed, or there is a solution such as the ones mentioned above available. If you’re having this problem, try them and fix your problem.