What is malware?

Malware is short for "malicious software." Malware is any kind of unwanted software that is installed without your adequate consent. Viruses, worms, and Trojan horses are examples of malicious software that are often grouped together and referred to as malware.

How to help protect your computer from malware

There are several free ways to help protect your computer against malware:

• Make sure automatic updating is turned on to get all the latest security updates.
• Keep your firewall turned on.
• Don't open spam email messages or click links on suspicious websites.
• Download Microsoft Security Essentials, which is free, or another reputable antivirus and anti-malware program. If you run Windows 8 or Windows RT, you don’t need Microsoft Security Essentials. (see the warning below).
• Scan your computer with the Microsoft Safety Scanner.

Warning: Cybercriminals sometimes try to trick you into downloading rogue (fake) security software that claims to protect you against malware. This rogue security software might ask you to pay for a fake product, install malware on your computer, or steal your personal information.

Don't click links in email messages and avoid websites that offer free software—especially free antivirus software.