How to Delete Windows Defender Error Code: 0x800b0003 From PC System?

Victim 1: "I open my computer (ASUS) the system is window 7 but now upgrade to win 10 enter the renew choice but my monitor displays error:0x80070003.may someone can help me?"

Victim 2: "windows defender will not activate in my windows 10 gives Error code: 0x800b0003...."

Brief information of Windows DefenderError Code: 0x800b0003

Windows DefenderError Code: 0x800b0003 appears when you try to retrieve updates through online Windows Update and when it is almost done. You usually get a sudden error saying some updates were not installed and Errors found: Code 80070539 Windows Update Encountered an unknown Error and the update fails. In fact, this error is caused by compatibility issue or is a sign that your PC might be infected with some malware, spyware or adware.


Once infected, your PC will appear a lot of symptoms:

1. Your PC performance and security can be degraded.
2. Your system become more and more vulnerable for other malware or viruses.
3. System files are corrupted and then result in the whole system mess up.
4. Malicious files and registry entries are injected to your system without your consent.
5. Your confidential information can be exposed and stolen for commercial purposes.

To avoid possible issues that may be aroused to cripple your system, you are highly advised to rid this invader immediately. If you are not skilled in dealing with manual removal by yourself, you could feel at ease to carry out the following removal tutorials.

Windows defenderError code: 0x800b0003 Removal Instructions

Method 1: Remove Windows defenderError code: 0x800b0003 from your PC manually

A: Get into the safe mode with networking
B: Stop all the related processes of Windows defenderError code: 0x800b0003.
C: Open Control Panel from Start menu and search for Folder Options.
D: Delete all the related registry entries

Method 2: Fix Windows Defender Error Code: 0x800b0003 and optimize your PC with RegCure Pro

Method 1: Remove Windows defenderError code: 0x800b0003 from your PC manually

A: Get into the safe mode with networking

<Restart your computer. As your computer restarts but before Windows launches, tap "F8" key constantly. Use the arrow keys to highlight the "Safe Mode with Networking" option, and then press ENTER>

B: Stop all the related processes of Windows defenderError code: 0x800b0003.

Press Ctrl+Alt+Del together to open Task Manager -> click on processes and tick Processes from all users box -> click on End Process to end all processes 

C: Open Control Panel from Start menu and search for Folder Options.

When Folder Options window opens, click on its View tab, tick Show hidden files and folders and non-tick Hide protected operating system files (Recommended) and then press OK.

D: Delete all the related registry entries 

Press Windows+R to launch Run…-> type Regedit into Open box and click OK to open Registry Editor-> find out all registry entries above and delete them

Find out all harmful registry entries of the virus and delete all of them:

HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Run "<random>" = "%AppData%\<random>.exe"

HKEY_LOCAL_MACHINE\Software\Microsoft\Windows\CurrentVersion\Run "<random>" = "%AppData%\<random>.exe"

HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Settings

HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Policies\Associations

Method 2: Fix Windows Defender Error Code: 0x800b0003 and optimize your PC with RegCure Pro

Malware prevention and removal is good. But when it comes to computer maintenance, it is far from enough. To have a better performance, you are supposed to do more works. If you need assistant with windows errors, junk files, invalid registry and startup boost etc, you could use RegCure Pro for professional help.

Step 1. Download PC cleaner RegCure Pro

 a) Click the icon below to download RegCure Pro automatically

 b) Follow the instructions to finish RegCure Pro installation process

Step 2. Run RegCure Pro and start a System Scan on your PC.

Step 3. Use the in-built “Fix All" scheduler to automate the whole optimization process.

Warm tip:

After using these methods, your computer should be free of Windows defenderError code: 0x800b0003. If you do not have much experience to remove it manually, it is suggested that you should download RegCure Pro to help you quickly and automatically remove all possible infections from your computer.