Does Windows Defender Run a Scan by Itself?

By Thomas King

Spyware may slow your computer to a crawl.
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Windows Defender is an anti-spyware program created by Microsoft and included with the Windows Vista and 7 operating systems. Windows Defender scans your computer and removes any spyware it detects. These scans can be run manually or scheduled to run automatically. In addition, you can decide the thoroughness of the scans.

What Is Spyware?

Spyware is a term used to describe malicious programs that perform certain tasks. These tasks include advertising, collecting personal information and changing the configuration of your computer. Moreover, spyware may slow your computer, decrease your available system memory and change your system configurations. Generally, spyware programs install themselves on your computer and perform these tasks without your consent.

Manual Scan

At any point, you can tell Windows Defender to scan your computer for spyware. This type of scan, referred to as a manual scan, may be necessary if you suspect your computer has become infected with spyware. For example, you may notice an inordinate amount of pop-ups or you may have just visited a suspicious website. To run a manual scan, open Windows Defender, click the "down arrow" next to "Scan" and select "Full Scan" or "Quick Scan." A full scan scans your entire computer for spyware, whereas a quick scan scans the places on your computer spyware is most likely to infect.

Automatic Scan

You can program Windows Defender to automatically scan your computer. This is beneficial because it keeps you from having to remember to scan your computer periodically. To program automatic scans, open Windows Defender, click "Tools" and "Options." Under "Automatic Scanning," check the box next to "Automatically Scan My Computer (Recommended)" and select the frequency, time of day and type of scan you want Windows Defender to run automatically. Note Windows recommends you run a daily "Quick Scan" at minimum.

Real-Time Protection

Windows Defender features a tool called "Real-Time Protection," which is a form of automatic scanning. This tool involves Windows Defender scanning all incoming data and alerting you when potentially dangerous or unwanted software is attempting to install itself or run on your computer. Thus, while the aforementioned scans are used to remove spyware from your computer, "Real-Time Protection" is designed to prevent spyware from infecting your computer in the first place.