Microsoft Security Essentials is the most reliable antivirus ever released In fact it is a great job by Microsoft Corporation to provide an antivirus to the Windows users at free of cost. Though it is very harmful for the third party security companies.
Windows 7 users can easily install MSE on their computers. But if you're using Windows XP then you may face problem installing it on your system. To install MSE on Windows XP SP 2 you need some additional files.
To install MSE on XP SP 2 download the file below. Then install all the three files of the folder. Then install MSE. If your XP is service pack 3 then install only the first file.
If you use Windows 8 then you don't need any third party security software. Because it has built in security system.
To know more about Microsoft Security Essentials click here.