Antimalware and cybersecurity portal - Windows Defender Security Intelligence

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What's new in Windows Defender ATP: new attack surface reduction rules, emergency security intelligence updates, incidents view, threat analytics, and more Read about all the new capabilities in Windows Defender ATP

Proven next-gen antivirus
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Detect. Investigate. Respond.
Defend against targeted attacks with Windows Defender Advanced Threat Protection
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Learn about ransomware
Get everything you need to know about ransomware
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Avoid tech support scams
Understand how scammers trick you into paying for fake tech support
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Explore our in-depth threat encyclopedia for information about threat types and specific malware

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Enable Windows Defender Antivirus
Keep your PC safer with the free, trusted antivirus protection built in to Windows 10.
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Sign up for Windows Defender ATP
Detect, investigate, and respond to targeted attacks in the enterprise using cloud-based behavioral analytics.
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Get Microsoft Security Software
Stay safer with the right security software that works effectively with Windows.
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Boost defenses with Windows Defender Exploit Guard
Get enhanced protection against ransomware and advanced attacks involving exploits, tainted documents and scripts, and code injection.
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Troubleshoot malware detection and removal
Resolve problems with detecting and removing persistent threats.
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Visit the help center
Explore our collection of helpful security advice to keep your computers safe.
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