Error 0x8050800c: Fix this error in Windows Defender

Why does error 0x8050800c appear in Windows Defender

In case you don’t know, Windows Defender is the free and default antivirus offered by Microsoft’s operating system. In Windows 10 this antivirus tool is capable of automatically performing scans and eliminating harmful infections that affect our computer. One of the most worrisome messages that we can face with Windows Defender is the error code 0x8050800c. When this failure happens, it will show us a screen like this:

It is a worrying failure because it leaves our Windows computer in a vulnerable situation in which we will not be protected from harmful software. This error code usually occurs in some situations like the ones listed below:

1. When we try to use Windows Defender.
2. A real-time scan is run.
3. When installing security updates.

The error message tells us that an unexpected problem has occurred, that we install the available updates and then try to start the program again.

As for the causes for which we find the error 0x8050800c, sometimes it has to do with third-party antivirus on your Windows computer. This happens because after uninstallation there are some traces of antivirus software that prevent Windows Defender from running. However, this would not be the only cause, it could also be due to security updates that are corrupted or out of date. Nor should we forget that the failure may be in the Windows registry or a file in the operating system has been corrupted.

Install the latest Windows updates

The error code 0x8050800c in its bug report advised us to install the latest available updates and then try to start the program. Therefore, we will follow your instructions and proceed as follows:

1. Let’s go to Start Menu Windows.
2. We type Search for updates and we press Enter.

Then we would see a screen like this:

Here you can see how an update for Microsoft Antivirus is being downloaded. Therefore, the cause of the failure could be here, although there is a possibility that it is not. For that reason we will also offer alternative solutions.

Once all the updates are installed, we restart in case any changes have to be applied. After Windows starts we will check if there is a new one, sometimes until a specific one is installed, it will not allow the next one to be installed. We will repeat it several times until there is no update available or there is one that, for some reason, does not allow it to install. Then we will have to think about evaluating other alternatives, or if everything has gone well, we will check if Windows Defender already works well.

Disable periodic Windows Defender scan

Another solution that can fix the error 0x8050800c is to proceed to disable the periodic Windows Defender scan. To perform this task we have to follow a series of steps:

1. We press the Windows key + I to go to Setting.
2. There we choose the option Updates and Security.
3. Then we choose Windows security.
4. Then we click on Virus and threat protection.

Then we will see a screen like this:

Here all we have to do is uncheck the «Periodic examination«. In this case, for this option to appear, it is required that you have a third-party antivirus installed, that is, outside of Microsoft.

Problems related to third-party antivirus software

This error 0x8050800c, as we have already mentioned before, may have to do with third-party antivirus software that we have installed on our computer. Sometimes, after the uninstallation, there are remains of the program that can impair the good performance of other programs. If we find ourselves in this situation, we have to check if the developer of that software that we had previously installed has a removal tool specific to delete all files related to that antivirus program.

We must not rule out that the problem is triggered by a third-party antivirus that we still have on our computer, so another possibility could be its uninstallation, there are “antimalware” security programs such as AntimalwareBytes that make Microsoft’s antivirus deactivate from the system, the same goes for the popular Acronis True Image by incorporating a security module. Any program that has a “security” part for our operating system could be the cause of this problem with Windows Defender, and we have to completely uninstall it to isolate the problem and find it.

Try running a DSIM scan

Another possible trigger for the problem is that we might have some corrupted Windows files. To solve this problem, we could use a native Windows tool called DSIM. This can be used to solve multiple problems including error code 0x8050800c. For this we are going to Windows menu, we wrote Symbol of the system and with the right button we execute it as administrator.

Once in the “Command Prompt” window we enter the following command:

DISM.exe /Online /Cleanup-image /Restorehealth

And we press enter to start its execution:

At that moment, a procedure that can last several minutes begins and that could solve this failure.

Start “clean” Windows using original startup

Another solution we could try is a “clean” Windows startup, thus using a minimal set of drivers and startup programs. Thanks to this, it could help us to eliminate software conflicts that occur when installing a program or an update in Windows. It is an option that we should not rule out to solve the error 0x8050800c. To do this, we will follow these steps:

1. We press Windows + R.
2. Then a window pops up to Run. We wrote msconfig and we press enter.

Then we will see a screen like this, and in the tab general we will choose Selective start. There we select Load system services and Use original startup settings.

Then we go to the tab Services and we activate the box Hide all Microsoft services. Now we click on Disable all.

Finally, click on the button To accept and we restart the computer. If after doing this everything works fine, then what you have to do is find out which of these services is causing the error 0x8050800c.

We hope that with this guide you have been able to solve this Windows Defender error that is quite common, if you continue having problems with this error, it is possible that a system restore to a previous state will solve the problem, or directly restore a backup where yes it worked properly and without problems.