Full Fix: Windows Defender Error Code 0x800b0100

Many users have complained that they are getting stuck with the error code 0x800b0100 while opening the Windows Defender program. Some are facing this error during the installation of this security software.

This error can occur due to various factors. In case, if your device has been infected by malware or virus infection, then such Windows Defender error can appear. It also occurs if there is any suspicious application that might conflict with your device. 

Once this error appears on the screen, users are not able to initiate the Windows Defender application. So, if you are in the same situation and looking for some reliable fixes, then you have hit the right page. 

In this article, we are going to mention all the best possible hacks to mitigate this Windows Defender Error Code 0x800b0100. So without further delay, let’s proceed with the troubleshooting section.

Troubleshooting Tips For Windows Defender Error Code 0x800b0100

There are multiple ways, which can resolve the Windows Defender error. But, in this section, we are going to share some of the most reliable methods. So, you can follow the steps in the same order as instructed to remove error 0x800b0100.

1. Execute a Clean Boot

Executing a clean booting process can be one of the most robust steps to remove such kind of error while opening the Windows Defender application. Starting your device with a minimum amount of applications and services can help you to resolve the matter. Hence, you can try this solution by performing a clean booting process.

If Windows Defender error appears due to any third-party application, then by using this method you get to know the actual culprit behind this error. As this process will disable all the third-party programs, to ensure that the device is safely booted.

But if you do not know how to perform a clean booting process, then follow the below section.

Step to Perform a Clean Boot:

• Press the Windows Logo key along with the R key. Then, write “MSConfig” into the Run dialog box and hit the Enter key to execute the command. 
• Now, find the “Sevice” tab that appears on the screen and click the “System Configuration” window. 
• Make the necessary changes to it and locate the “Hide all Microsoft Service” option. Once you find it, click on it and place a tick mark on the checkbox.
• Since all the Microsoft related services are hidden, tap on the “Disable All” button. It is located at the bottom-right corner.
• Next, navigate to the “Startup” tab and hit the “Task Manager” option to open the window.
• Choose those applications that belong to third-party resources. Right-click on them one by one and hit the “Disable” option. 
• Once the process is over, close the Task Manager window and choose the OK button to save the new changes.

Now, your PC will boot with the minimum amount of features and applications. Check whether the error gets removed or not.

If you do not find the error anymore, that’s mean, any third-party application causing this issue. To know the exact reason, you can reset the settings as they were. So, go through these steps.

Steps to Revert the New Modifications:

Launch the System Configuration window by following the above steps. Then, choose the “General” tab to view the internal settings.

After that, choose the “Normal Startup” option from the resultant menu and hit the “Service” tab.

Now, find the “Hide all Microsoft Services” option and tap on it to remove the tickmark. 

Further, hit the “Enable All” button that is situated at the bottom-right portion of the window.

Go to the “Startup” tab and invoke the Task Manager window. Then, enable all the applications one by one and check which one is triggering the Windows Defender error.

In this way, you can easily revert all the new modifications. Now, you can boot your device in its normal mode. 

2. Run SFC Scan

Whenever you find this specific Windows Defender error, you should use the System File Checker tool to scan your device. This will examine your entire device and detect all the corrupted or damaged files. If error code 0x800b0100 occurs due to malware or virus infection, you can try this solution.

Many affected users have claimed that after running the System File Checker application, the Windows Defender error gets removed from there devices. To overcome this situation, you can also run the tool. Hence, follow the undermentioned steps to do this task.

• First, press the combination of the W indows Logo + R key. This will open the Run dialog window, where you need to write “cmd”. Hit the Enter tab and you will find the Command Prompt option at the top of the search result. 
• Right-click on it and hit the “Run as Administrator” option from the appeared menu. This action will launch the Command Prompt with Administrator’s privileges. Click on the Yes button if you are prompted by a new window.
• After that, write “sfc/scannow” into the Command Prompt window and press the Enter key to execute the command.

After performing this action, System File Checker will scan your entire device and look for the corrupted or damaged system files. Once it locates the corrupted system files, it will automatically repair them. Once the process is complete, reboot your device and verify whether the error still appears or not.

3. Try to Use DISM Scanning Tool

After running the SFC, if you still get the same Windows Defender error code 0x800b0100, then you can use the DISM scan. It is another built-in utility that comes up with all versions of Windows. To run the DISM application, you need to follow the undermentioned steps.

• Primarily, open the Command Prompt with Administrative privileges by following the above-discussed steps.
• Then, type the following command into the Command Prompt window and do not forget to hit the Enter button after entering the command. 

“dism.exe /Online /Cleanup-image /Restorehealth”

This procedure might take a few minutes to finish. So, be patient and do not interrupt the process in between.

4. Review the Windows Defender Service

If the above three methods haven’t fixed Windows Defender Error Code 0x800b0100, then you should check the program’s status. When the Windows Defender Service does not run properly, then such kind of error can appear.

In such situations, you need to ensure that the Windows Defender services are running. In most cases, due to the malware or virus infection, Windows Defender Service gets disabled even without notifying you.

So, you can follow the steps underneath to know the overall status of Windows Defender services.

Step 1: First, hold the Windows logo+ R key and invoke the Run dialog window. After that, type “services.msc” into the box and tap the Enter button to proceed further.

Step 2: It will initiate the “Services” window. Under this, try to find out the Windows Defender from the resultant menu list. Once you can locate it, double-click on the application. This will open a new window.

Step 3: Here, launch the Windows Defender Services and check the settings. Now, you need to be sure that the Startup Type is set as “Automatic”, which is situated at the top-left corner of the window. Moreover, confirm that the Windows Defender Service is in the workable state.

To Conclude:

In the above section, we have mentioned all the important information regarding the Windows Defender error code 0x800b0100. If you ever come across any other Windows Defender issue, then post your troubles in the feedback section below. We will surely help you out.

Moreover, if you want to know more about this Windows Defender error  0x800b0100, then leave your queries or contact us for advanced fixes.