FIX: Windows Defender service won't get-go on Windows 10/11

Madalina has been a Windows fan always since she got her hands on her first Windows XP calculator. She is interested in all things applied science, especially emerging technologies -- AI and DNA computing in... Read more

Updated:

Posted: May 2021

  • If the Windows Defender cannot be started, you're left open to cyber-attacks and viruses.
  • Make sure to remove or disable any third-party antivirus solutions on the device.
  • Install the latest Windows and driver updates, and always keep them upwardly-to-date.
  • You could as well perform a System File Check browse and let the OS fix any detected issues.

fix windows defender not starting

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Windows Defender is one of the most pop antivirus programs worldwide, protecting millions of computers against vicious threads. Yet, many users report that their Windows Defender cannot be started.

Oftentimes, when users try to start Microsoft's congenital-in antivirus, an error message appears on the screen informing them that the service couldn't exist started.

Many Windows 10 users reported that the Windows Defender service won't outset on their PC at all. Moreover, here are some other similar issues that users reported. and speaking of problems with Windows Defender.

  • Windows Defender service won't first Windows 10, 8, 7 – According to users, this problem tin appear on all versions of Windows, including both Windows 8 and 7. Fifty-fifty if you don't apply Windows 10, you should know that almost all of our solutions are compatible with older versions of Windows, so feel free to try them.
  • Windows Defender service won't start error 577 – Sometimes mistake 577 can appear while trying to start Windows Defender service. To fix this problem, make sure that y'all don't have any 3rd-party antivirus installed on your organization.
  • Windows Defender Security Eye won't open up – Several users reported that Windows Defender Security Centre won't open at all. To prepare this issue, check if you accept the latest updates installed.
  • Windows Defender service won't kickoff access denied – This problem tin can appear due to problems with your permissions. To fix the problem, you demand to adapt the security permissions of ProgramDataMicrosoft directory.
  • Windows Defender service keeps stopping – If Windows Defender service keeps stopping, the issue might be contour corruption. Only create a new user contour and check if that solves the problem.

Windows Defender service won't start, how to fix information technology?

i. Disable and remove third-political party antivirus solutions

Running two antivirus solutions at the same time causes diverse technical bug. Use dedicated software removal tools to completely remove any tertiary-political party antivirus files.

If yous don't manage to fix the problem, you lot can always switch to a third-party antivirus solution. At that place are many great antivirus tools, and yous should look for one that has lots of security features.

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2. Install the latest Windows Updates

  1. Press Windows Key + I to open the Settings app.
  2. Now go to Update & Security department.
  3. Click Check for updates button.
    Windows Defender service won't start Windows 7

Windows will at present check for available updates and download them in the background. Once the updates are downloaded, simply restart your PC to install them.

Sometimes you might be able to prepare the Windows Defender service non starting simply by installing the latest updates. By keeping your organization up to engagement, you'll ensure that everything is running smoothly on your PC.

Windows 10 unremarkably downloads the necessary updates automatically in the background, but due to certain bugs, y'all might skip an update or two.

3. Run an SFC scan

  1. Printing Windows Central + X to open up Win + X bill of fare. Now select Command Prompt (Admin) or Powershell (Admin).
    Windows Defender service won't start Windows 8.1
  2. When Control Prompt opens, enter the following command and printing Enter: sfc /scannow
    Windows Defender service keeps stopping
  3. SFC scan will at present showtime. The browse can take up to 15 minutes, so don't interrupt it.

According to users, sometimes Windows Defender service won't beginning because of file corruption. Your system files tin can get corrupted and that can crusade this error to appear.

In one case the scan is finished, check if the trouble still persists. If the event is even so present, or if you weren't able to run SFC browse at all, you might want to try running DISM scan instead.

  1. Open up Command Prompt as administrator.
  2. When Command Prompt opens, enter the following command: DISM /Online /Cleanup-Paradigm /RestoreHealth
    Windows Defender service won't start error 577
  3. DISM scan will now start. The scan tin have up to 20 minutes, sometimes more, and so you need to be patient and not interrupt it.

One time the DISM scan is finished, check if the problem still persists. If the problem is still at that place or if you couldn't run DISM browse before, exist sure to echo SFC scan and check if that solves the trouble.

4. Make clean your registry

Sometimes the Windows Defender cannot exist started if in that location are issues with your registry. A corrupted registry entry can cause this issue to appear and you demand to discover and remove the problematic entry.

This is a complex task to perform manually, so it'south better to use special software for it. At that place are many smashing registry cleaners available that can help you with that trouble.

To find the proper choice for this task you lot can opt for efficient registry cleaner tools that eliminate rest files and optimize your PC.

5. Check your environment variables

  1. Press Windows Key + S and enter advanced organization settings. Select View avant-garde organization settings from the menu.
    Windows Defender service won't start access denied
  2. At present click Environment Variables button.
    Windows Defender service keeps stopping
  3. Locate %ProgramData% variable and check if it'south set to C:ProgramData.
    • If non, change the variable appropriately.

Skillful Tip: Some PC issues are hard to tackle, specially when it comes to corrupted repositories or missing Windows files. If you are having troubles fixing an error, your system may exist partially broken. We recommend installing Restoro, a tool that will browse your machine and identify what the mistake is.
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Surround variables are a useful feature that your organisation uses in social club to access certain directories.

However, sometimes users or perchance third-party applications can modify your environment variables and cause this upshot to appear.

This will make it so you lot cannot start the Windows Defender service but you can fix your surroundings variables manually past doing the following:

After making these changes, the trouble should be resolved and Windows Defender should beginning working.

6. Alter system permissions

  1. Get to the following directory: C:ProgramData
  2. Now locate the Microsoft directory and right-click it. Cull Backdrop from the carte.
    Windows Defender Security Center won't open
  3. Now go to the Security tab and click Advanced.
    Windows Defender service won't start access denied
  4. Now yous should remove all inherited permissions. Later doing that, relieve the changes and check if the problem is resolved.

According to users, sometimes your folder permissions tin can lead to this problem. If Windows Defender service won't outset on your PC, you might have to change your permissions.

This is an advanced procedure, and if you're not familiar with permissions, you might want to skip this solution.

Keep in mind that this is a arrangement folder, and whatsoever changes to this folder tin can crusade bug to appear, and then if y'all're not familiar with system permissions, you might desire to skip this solution.

7. Create a new user account

  1. Open the Settings app and go to the Accounts department.

    Windows Defender service won't start error 577
  2. Go to Family unit & other people on the menu on the left. In the right pane, click Add someone else to this PC.
    Windows Defender Security Center won't open
  3. Click I don't have this person's sign-in information.
    Windows Defender service won't start Windows 10
  4. At present select Add a user without a Microsoft business relationship.
    Windows Defender service won't start error 577
  5. Enter the desired user name and click Next.
    Windows Defender Security Center won't open

If the Windows Defender service won't get-go, yous might be able to ready the problem just by creating a new user business relationship.

Sometimes your user account tin become corrupted and that can cause this and other errors to appear. To fix the problems with a user account, follow the instructions above.

Later creating a new user account, switch to it and bank check if the trouble is however present. If not, you might have to switch to the newly created business relationship and start using it instead of your old i.

8. Perform an in-identify upgrade

  1. Download Media Creation Tool from Microsoft'southward website and run it.
  2. Select Upgrade this PC now.
  3. Wait while setup prepares the necessary files.
  4. Select Download and install updates (recommended). Expect while the setup downloads the necessary files.
  5. Follow the instructions on the screen until you reach the Ready to install screen.
  6. Make sure that Keep personal files and apps appears on the recap list.
    • If not, click Change what to keep and select Keep personal files and apps from the listing.
  7. Follow the instructions on the screen to consummate the installation.

If the previous solutions didn't fix the problem, yous tin can try performing an in-place upgrade. By doing and then, you'll reinstall Windows 10, but you lot'll go on all your files and applications.

Once the installation is finished, yous'll have a fresh installation of Windows and the problem should be resolved.

Ane last thing earlier we wrap upward the article. If you're looking for a new antivirus tool, have a look at this helpful list of the best antivirus tools with lifetime license and cull from there.

Not existence able to start the Windows Defender service tin can be a trouble, but we hope you managed to prepare this issue with i of our solutions.