The most noticeable change in the version update is the updated tray icon showing a check mark on a green background when the settings indicate that the computer status is "Protected". Turning off, for example, the real-time protection results in the icon turning red with an X and the message that the Computer is "At risk".
Reported Accessibility Improvements: "Tab and Crtl+Tab functions cycle focus from the tab (labeled as a button), though all of the controls on that page then back up to the tab. Left and Right Arrows navigate between the tabs."
Because Microsoft Security Essentials is still in Beta, it is expected that any other changes were bug fixes.
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