microsoft defender antivirus for windows 10

learn.microsoft.com › en-us › answers › questions › 2285052 › how-to-install-windows-defender

Hello @Zig Zag ,

Thank you for posting your query on Q&A forum.

Install Windows Defender on Windows PC:

Windows Defender is built into Windows 10 and Windows 11, so you don’t need to download or install it. You just need to enable it if it’s turned off.

Step 1: Check if Windows Defender is Already Installed

Open Windows Security: Press Windows + S and search for Windows Security, then open it.
Check for Protection: Click **"Virus & threat protection". If you see Microsoft Defender Antivirus listed and active, it’s already working.

Step 2: Enable Windows Defender (If It’s Disabled)

If you recently removed a third-party antivirus (like Norton), Defender may still be off. To re-enable it:

Open Settings:

Press Windows + I >> go to Privacy & Security >> Windows Security >> Open Windows Security.

Go to Virus & Threat Protection: Click "Manage settings" under Virus & threat protection settings.
Turn On These Settings:

Real-time protection – Toggle ON.
Cloud-delivered protection – Toggle ON.
Automatic sample submission – Toggle ON.

Step 3: Restart Your PC

After making changes, restart your PC to fully activate Microsoft Defender.

Optional: Set Microsoft Defender as Default

If Windows Defender doesn’t automatically become your default antivirus:

Go to Start > Settings > Apps > Default apps and check that Defender is set as your virus scanner.

Step 4: Test That It’s Working

Go to **Windows Security > Virus & threat protection.
Click Quick Scan to ensure it’s scanning and active.

Once, the above steps are followed then, you can proceed to delete any other third-party Antivirus from the PC.

Here are the steps to completely delete Norton Antivirus from a Windows PC:

Uninstall via Windows Settings

Open Settings

Press "Windows + I" or click the Start menu > Settings.

Go to Apps

Click Apps > Installed apps (or Apps & features in older versions).

Find Norton Antivirus

Scroll or search for "Norton" (e.g., Norton Security, Norton 360).

Uninstall

Click on the Norton product > click Uninstall > confirm and follow the prompts.

Restart your PC if prompted.

Make sure you have admin rights on your PC.
Backup any license keys or subscriptions if you plan to reinstall Norton later.

I hope this information is helpful. Please feel free to reach out if you have any further questions.

If the answer is helpful, please click "Accept Answer" and kindly upvote it. If you have extra questions about this answer, please click "Comment".

Microsoft Store

apps.microsoft.com › detail › 9p6pmztm93lr

Microsoft Defender - Free download and install on Windows | Microsoft Store

November 3, 2025 - Microsoft Defender is a security app for individuals and families that helps protect identities, data, and devices from online threats. The Microsoft Defender app is available exclusively with a Microsoft ...

Microsoft Learn

learn.microsoft.com › en-us › defender-endpoint › office-365-microsoft-defender-antivirus

Better together - Microsoft Defender Antivirus and Office 365 (including OneDrive) - better protection from ransomware and cyberthreats - Microsoft Defender for Endpoint | Microsoft Learn

October 22, 2025 - Applies to: Microsoft Defender for Endpoint Plan 1, Microsoft Defender for Endpoint Plan 2 ... Microsoft Defender Antivirus protects your Windows device from software threats, such as viruses, malware, and spyware.

Discussions

how to install windows defender

Windows Defender is built into Windows 10 and Windows 11, so you don’t need to download or install it. You just need to enable it if it’s turned off. Step 1: Check if Windows Defender is Already Installed · Open Windows Security: Press Windows + S and search for Windows Security, then open it. Check for Protection: Click **"Virus & threat protection". If you see Microsoft Defender Antivirus ... More on learn.microsoft.com

learn.microsoft.com

June 17, 2025

Is Microsoft Defender "enough" for basic virus and malware protection on a home PC?

If you suspect you may have malware on your computer, or are trying to remove malware from your computer, please see our malware guide Please ignore this message if the advice is not relevant. I am a bot, and this action was performed automatically. Please contact the moderators of this subreddit if you have any questions or concerns. More on reddit.com

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January 28, 2025

Is Windows Defender enough protection?

I use and recommend Windows Defender over all third party solutions. It’s an excellent antivirus offering good performance and protection. This combined with uBlock Origin and safe practices and you’ll be in good shape.

Use Malwarebytes free and periodically run scans for extra protection.

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