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Antivirus programs are powerful pieces of software that are essential on Windows computers.
Related:What’s the Best Antivirus for Windows 10 and 11?
(Is Microsoft Defender Good Enough?)
On-Access Scanning
Antivirus software runs in the background on your gear, checking every file you open.
Antivirus programs also scan other types of files that can contain viruses.
For example,a .zip archive filemay contain compressed viruses, ora Word documentcan contain a malicious macro.
Overall results from July to October 2021.
After a virus has infected your system, it’smuch harder to remove.
(It’s also hard tobe sure that the malware has ever been completely removed.)
Full-system scanscan be useful for some things, however.
Most antivirus programsset up scheduled full system scans, often once a week.
This ensures that the latest virus definition files are used to scan your system for dormant viruses.
These full disk scans can also be helpful when repairing a computer.
Virus Definitions
Your antivirus software relies on virus definitions to detect malware.
The definition files contain signatures for viruses and other malware that have been encountered in the wild.
No antivirus program is perfect.
Overall results from July to October 2021.
This is known as a “false positive.”
Heuristics can also increase the rate of false positives.
Despite this,false positives are fairly rare in normal use.
If your antivirus says a file is malicious, you should generally believe it.
This allows you to test antivirus program responses without using a live virus.
