Microsoft has just released a new version of its free antivirus, Microsoft Security Essentials 4.2.223.1 for Windows 7, Windows Vista and Windows XP.
It's a major release but there's a problem -- If you are an existing MSE user, you will see an update KB2804527 in Windows Update. It is listed as "Update for Microsoft Security Essentials - KB2804527 (4.2.223.1)". Make sure to create a restore point before installing this update as a lot of people are getting an error (Error Code 8004FF80). MSE stops working if the update fails to install. So take care.
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