Windows Defender is a Microsoft security software product that is included in the Windows Vista and Windows 7 operating system. It is also available as an option download for the Windows XP system. The program is a anti-spyware program that can scan a computer system for malicious software and delete or quarantine the findings.
Windows Defender comes with the usual options to automatically update the program and schedule regular system scans to protect the computer system. Default actions for low, medium and high alerts can be defined that will be executed by the anti-spyware program automatically.
Microsoft's anti-spyware solution comes with the interesting advanced tool Software Explorer which can display extensive information about startup programs, currently running programs, network connected programs and Winsock service providers.
Each program and provider is sorted by company which makes it easier to find non-Microsoft programs that are running or connected to the computer system.
Microsoft has improved Windows Defender over the years. The company did receive lots of criticism in the beginning which can be attributed to a low spyware detection rate. Several anti-spyware products have performed better in tests, outlined here or here. Please note that the tests linked in this article have been performed about 10 months ago and that the situation may have changed in the mean time.
Which leads to the question: Are you running anti-spyware software? If so which?
Update: It seemed for a long time as if Microsoft Security Essentials would replace Windows Defender in the long run, but that apparently was not the case. Microsoft made the decision to integrate the capabilities of Security Essentials into Windows Defender on Windows 8. The program basically combines the capabilities of Microsoft Security Essentials and Windows Defender in one program. That's also the reason why Security Essentials is not available for Windows 8.Advertisement