Microsoft Defender Antivirus
Microsoft Defender Antivirus is an antivirus software component for Microsoft Windows and mobile. It was first released as a downloadable free anti-spyware program for Windows XP and was shipped with Windows Vista and Windows 7. It has evolved into a full antivirus program, replacing Microsoft Security Essentials in Windows 8 or later versions.
In March 2019, Microsoft announced Microsoft Defender ATP for Mac for business customers to protect their Mac devices from attacks on a corporate network, and a year later, to expand protection for mobile devices, it announced Microsoft Defender ATP for Android and iOS devices, which incorporates Microsoft SmartScreen, a firewall, and malware scanning. The mobile version of Microsoft Defender also includes a feature to block access to corporate data if it detects a malicious app is installed.
Microsoft Defender brand
As of 2021, Microsoft Defender Antivirus is part of the much larger Microsoft Defender brand, which includes several other software and service offerings, including:- Microsoft Defender XDR
- Microsoft Defender for Cloud
- Microsoft Defender Endpoint
- Microsoft Defender for Office 365
- Microsoft Defender for Identity
- Microsoft Defender for Cloud Apps
- Microsoft Defender Vulnerability Management
- Microsoft Defender for Threat Intelligence
- Microsoft Defender for Individuals
Features
Real-time protection
In the Windows Defender options, the user can configure real-time protection options. Windows 10's Anniversary Update introduced Limited Periodic Scanning, which optionally allows Windows Defender to scan a system periodically if another antivirus app is installed. It also introduced Block at First Sight, which uses machine learning to predict whether a file is malicious.Browser integration
Integration with Internet Explorer and Microsoft Edge enables files to be scanned as they are downloaded to detect malicious software inadvertently downloaded. As of April 2018, Microsoft Defender is also available for Google Chrome via an extension and works in conjunction with Google Safe Browsing, but as of late 2022, this extension is now deprecated.Application Guard
A feature released in early 2018, Windows Defender Application Guard is a feature exclusive to Microsoft Edge that allows users to sandbox their current browsing session from the system. This prevents a malicious website or malware from affecting the system and the browser. Application Guard is a feature only available on Windows 10/11 Pro and Enterprise. In May 2019, Microsoft announced Application Guard for Google Chrome and Firefox. The extension, once installed, will open the current tabs web page in Microsoft Edge with Application Guard enabled. In April 2024, Microsoft announced that Microsoft Defender Application Guard will be deprecated for Edge for Business. The Chrome and Firefox extensions will not be migrating to Manifest V3 and will be deprecated after May 2024.Controlled Folder Access
Controlled Folder Access is a feature introduced with Windows 10 Fall Creators Update to protect a user's important files from the growing threat of ransomware. This feature was released about a year later after the Petya family of ransomware first appeared. The feature will notify the user every time a program tries to access these folders and will be blocked unless given access via the user. Windows will warn the user with a User Account Control popup as a final warning if they opt to "Allow" a program to read Controlled Folders.Tamper Protection
Introduced in Windows 10 version 1903, Tamper Protection protects certain security settings, such as antivirus settings, from being disabled or changed by unauthorized programs.Antivirus updates
Updates of virus definitions are released under KB2267602.History
Microsoft AntiSpyware (Beta 1)
Windows Defender was initially based on GIANT AntiSpyware, formerly developed by GIANT Company Software, Inc. The company's acquisition was announced by Microsoft on December 16, 2004. While the original GIANT AntiSpyware officially supported older Windows versions, support for the Windows 9x line of operating systems was later dropped by Microsoft.The first beta release of Microsoft AntiSpyware from January 6, 2005, was a repackaged version of GIANT AntiSpyware. There were more builds released in 2005, with the last Beta 1 refresh released on November 21, 2005.
At the 2005 RSA Security conference, Bill Gates, the Chief Software Architect and co-founder of Microsoft, announced that Microsoft AntiSpyware would be made available free-of-charge to users with validly licensed Windows 2000, Windows XP, and Windows Server 2003 operating systems to secure their systems against the increasing malware threat.
Windows Defender (Beta 2)
On November 4, 2005, it was announced that Microsoft AntiSpyware was renamed to Windows Defender. Windows Defender was released on February 13, 2006. It featured the program's new name and a redesigned user interface. The core engine was rewritten in C++, unlike the original GIANT-developed AntiSpyware, which was written in Visual Basic. This improved the application's performance. Also, since Beta 2, the program works as a Windows service, unlike earlier releases, which enables the application to protect the system even when a user is not logged on. Beta 2 also requires Windows Genuine Advantage validation. However, Windows Defender did not contain some of the tools found in Microsoft AntiSpyware. Microsoft removed the System Inoculation, Secure Shredder and System Explorer tools found in MSAS as well as the Tracks Eraser tool, which allowed users to easily delete many different types of temporary files related to Internet Explorer 6, including HTTP cookies, web cache, and Windows Media Player playback history. German and Japanese versions of Windows Defender were later released by Microsoft.Windows Defender - Release
On October 23, 2006, Microsoft released the final version of Windows Defender. It supports Windows XP and Windows Server 2003; however, unlike the betas, it doesn't run on Windows 2000. Some of the key differences from the beta version are improved detection, redesigned user interface and delivery of definition updates via Automatic Updates.Windows Defender has the ability to remove installed ActiveX software. Windows Defender featured an integrated support for Microsoft SpyNet that allows users to report to Microsoft what they consider to be spyware, and what applications and device drivers they allow to be installed on their systems.
Windows Defender - Windows Vista
Windows Vista included several security functionalities related to the Windows Defender. Some of the functionality was removed in subsequent versions of Windows.Security agents
Security agents which monitor the computer for malicious activities:- Auto Start – Monitors lists of programs that are allowed to automatically run when the user starts the computer
- System Configuration – Monitors security-related settings in Windows
- Internet Explorer Add-ons – Monitors programs that automatically run when the user starts Internet Explorer
- Internet Explorer Configurations – Monitors browser security settings
- Internet Explorer Downloads – Monitors files and programs that are designed to work with Internet Explorer
- Services and Drivers – Monitors services and drivers as they interact with Windows and programs
- Application Execution – Monitors when programs start and any operations they perform while running
- Application Registration – Monitors tools and files in the operating system where programs can register to run at any time
- Windows Add-ons – Monitors add-on programs for Windows
Software Explorer
In each Explorer, every element is rated as either "Known", "Unknown" or "Potentially Unwanted". The first and last categories carry a link to learn more about the particular item, and the second category invites users to submit the program to Microsoft SpyNet for analysis by community members. The Software Explorer feature has been removed from Windows Defender in Windows 7.
Conversion to full antivirus
Windows Defender was released with Windows Vista and Windows 7, serving as their built-in anti-spyware component. In Windows Vista and Windows 7, Windows Defender was superseded by Microsoft Security Essentials, an antivirus product from Microsoft which provided protection against a wider range of malware. Upon installation, Microsoft Security Essentials disabled and replaced Windows Defender.In Windows 8, Microsoft upgraded Windows Defender into an antivirus program very similar to Microsoft Security Essentials for Windows 7, and it also uses the same anti-malware engine and virus definitions from MSE. Microsoft Security Essentials itself does not run on Windows versions beyond 7. In Windows 8 or later, Microsoft Defender Antivirus is on by default. It switches itself off upon installation of a third-party anti-virus package.
Following the consumer-end launch, Windows Server 2016 was the first version of Windows Server to include Windows Defender.