Windows Defender is a free program that helps protect your computer against pop-ups, slow performance, and security threats caused by spyware and other unwanted software. It features Real-Time Protection, a monitoring system that recommends actions against spyware when it's detected and minimizes interruptions and helps you stay productive.
The build is marked as 1.1.1592.0 and it seems it can be installed over top previous versions (Beta 2, It can not be installed over top Beta 1 previously known as Microsoft Anti-Spyware Beta).
The only noticeable changes are the minor color scheme updates to the User Interface (Previously a Light Blue > Dark Blue gradient, now a Blue > Green gradient.) And as well a new option to display the System Tray Icon even when the program is not in the process of updating or scanning the computer. Other changes include more improvements to the scanning engine as well as an improved Software Explorer.
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