How to Fix Windows Defender Error 0x800b0100? [Fixed 2024]

How I do Fix Windows Defender Error 0x800b0100? Windows Defender is a built-in feature of Windows 10 that guards against viruses and malware on the computer. However, what if there is a mistake?

Yes, when you try to launch Windows Defender, an error warning appears.

An error has occurred in the program during initialization. If this problem continues, please contact your system administrator.

Error Code: 0x800b0100

When your system has corrupt system files or is infected with malware or viruses, this error message appears. You must be dealing with a number of problems if you are also tackling the mistake.

Error 0x800b0100 in Windows Defender Users using Windows 10 are unable to activate Windows Defender.

As a result, you must use some of the fixes offered in this article to correct this problem. Examine them, remove the 0x800b0100 error, and then activate Windows Defender.

How to Fix Windows Defender Error 0x800b0100?

The solutions provided below will assist you in quickly resolving the Windows Defender problem 0x800b0100 on Windows 10, and you can continue to utilise Windows Defender to safeguard your computer.

Solution 1: Check the Windows Defender Service

Verify if the Windows Defender service is active by checking its status. Windows Defender error code 0x800b0100 frequently occurs when the defender is turned off as a result of a third-party program infection.

Therefore, you must ensure that Windows Defender is turned on in order to resolve the problem code 0x800b0100. To do so, adhere to these steps:

  • Tap the Windows key plus R, type services.msc, and select OK.
  • Look up Windows Defender.
  • To check if the Windows Defender service is starting automatically or not, double-click on it.

Additionally, confirm whether the following services are running or not.

Windows Defender Advanced Threat Protection Service

Windows Defender Network Inspection Service

  • Verify that the aforementioned services are activated and functioning in automatic startup mode.

Check to see if Windows Defender is operating correctly and that the 0x800b0100 issue can be avoided when you launch it after performing the aforementioned procedures.

Solution 2: Perform SFC Scan

Windows Defender error 0x800b0100 is one of the errors that can occasionally occur on Windows due to missing or corrupt system files.

Therefore, you must run a system file checker (SFC) scan in order to resolve this problem. To complete the scan, adhere to the instructions below:

  • Select “Cortana search.”
  • When you type cmd, the result will appear. Right-click and choose “run as administrator.”
  • Type sfc/scannow into the command prompt window and hit the Enter key.

As the scanning procedure finishes, give it some time to replace all of your corrupted and missing files.

After scanning is complete, attempt to launch Windows Defender again without receiving the error number 0x800b0100: Windows Defender is not operating.

Solution 3: Run the DISM command

If the Windows Defender problem 0x800b0100 persists even after running the SFC scan, you can try using the DISM command to fix it.

To run the DISM command, stick to these steps:

Select “Cortana search.”
When you type cmd, the result will appear. Right-click and choose “run as administrator.”

Enter the following command in the command prompt window, pressing Enter after each word:

DISM /Online /Cleanup-Image /CheckHealth

Dism /Online /Cleanup-Image /ScanHealth

DISM /Online /Cleanup-Image /RestoreHealth

Be patient as you wait for the scanning process to finish; it may take some time.

When you launch Windows Defender on your computer once the scanning is finished, the Windows Defender error 0x800b0100 Windows 10 won’t appear.

Solution 4: Restart the Windows Update Components

Try restarting the Windows update component to resolve the fault if your Windows Defender is malfunctioning on Windows 10 and displays the warning “Windows Defender, an error has occurred during initialization” (0x800b0100) on your screen.

Make a backup of your registry before attempting to restart the Windows update components, as you might need to change a few registry entries.

Observe these actions to continue the process:

  • Click the Windows symbol.
  • Choose Command Prompt (Admin) after typing cmd.
  • If the user account control window appears, click yes.

To halt Windows updates, BITS, cryptographic, and MSI Installer services, type the following command and hit Enter:

net stop bits
net stop wuauserv
net stop appidsvc
net stop cryptsvc

To remove the qmgr*.dat files, enter the following command now:

“%ALLUSERSPROFILE%\Application Data\Microsoft\Network\Downloader\qmgr*.dat”

After completing the aforementioned tasks, execute the command cd /d %windir%\system32 and hit Enter.

Re-register the BITS and Windows Update files at this time by typing the following commands and hitting the enter key after each one:

regsvr32.exe atl.dll

regsvr32.exe urlmon.dll

regsvr32.exe mshtml.dll

regsvr32.exe shdocvw.dll

regsvr32.exe browseui.dll

regsvr32.exe jscript.dll

regsvr32.exe vbscript.dll

regsvr32.exe scrrun.dll

regsvr32.exe msxml.dll

regsvr32.exe msxml3.dll

regsvr32.exe msxml6.dll

regsvr32.exe actxprxy.dll

regsvr32.exe softpub.dll

regsvr32.exe wintrust.dll

regsvr32.exe dssenh.dll

regsvr32.exe rsaenh.dll

regsvr32.exe gpkcsp.dll

regsvr32.exe sccbase.dll

regsvr32.exe slbcsp.dll

regsvr32.exe cryptdlg.dll

regsvr32.exe oleaut32.dll

regsvr32.exe ole32.dll

regsvr32.exe shell32.dll

regsvr32.exe initpki.dll

regsvr32.exe wuapi.dll

regsvr32.exe wuaueng.dll

regsvr32.exe wuaueng1.dll

regsvr32.exe wucltui.dll

regsvr32.exe wups.dll

regsvr32.exe wups2.dll

regsvr32.exe wuweb.dll

regsvr32.exe qmgr.dll

regsvr32.exe qmgrprxy.dll

regsvr32.exe wucltux.dll

regsvr32.exe muweb.dll

regsvr32.exe wuwebv.dll

Reset Winsock after completing the aforementioned steps. In order to do it, type the following command and hit the enter key as normal:

netsh winsock reset

netsh winhttp reset proxy

Enter the following commands to restart Windows Update, MSI Installer services, BITS, and cryptography. Don’t forget to hit Enter after each command.

net start bits

net start wuauserv

net start appidsvc

net start cryptsvc

following the completion of all operations and the reset of the Windows update components. Error 0x800b0100 in Windows Defender won’t show up anymore.

Solution 5: Perform a Clean Boot

You can find out which third-party application is preventing Windows Defender from operating correctly and displaying the error code 0x800b0100 by doing a clean boot.

The steps to carry out a clean boot are as follows:

  • Toggle the Windows+R key.
  • Enter msconfig and press Enter.
  • Select the Services tab.
  • Verify the option to “Hide All Microsoft Services.”
  • Select “Disable All.”
  • Click the Startup tab now.
  • Select Task Manager, then give it a right-click.
  • Choose every startup item, then select “Disable all.”
  • To save your changes, click OK.
  • Turn your computer back on.

The Windows Defender is not working error code 0x800b0100 issue should be fixed by completing the aforementioned procedures.

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Alright, I’ve done everything I can to compile the answers that will enable you to resolve the Error Code 0x800b0100: Windows Defender is not working.

The Windows Defender problem 0x800b0100 will undoubtedly be fixed by using the methods in this article. However, if none of them work, use the simple fixes to quickly and easily fix the mistake.

It is anticipated that you found this article to be interesting and that it answered some of your questions about the error.

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