Antivirus and firewall for beginners

In short: Antivirus detects malware, the firewall controls connections into and out of the network. On Windows, Microsoft Defender and the built-in firewall are enough for many users, as long as they stay active.

In more detail: Malware (viruses, trojans, ransomware) reaches the computer through attachments, downloads and websites. The best protection is caution plus up-to-date software; the virus scanner is the safety net.

In Depth

• Microsoft Defender: Included in Windows and active. Find it under “Windows Security”.
• Second scanner: Do not run several antivirus programs at once, they interfere.
• Firewall: Blocks unwanted access. Leave it on.
• Scan: Run a full scan regularly or when in doubt.
• Take warnings seriously: Browser messages like “Your PC is infected, call us” are scams.
• Ransomware: Encrypts files and demands money. Best countermeasure: a backup.
• Not needed: Expensive “optimisers” or add-on bundles.

See also: Backups for beginners, Installing updates: why and how