Nov 21, · Microsoft Security Essentials is available in many locales and languages. If it is not available in your preferred language, you can install it in any of the other languages listed here, and it will still work to help protect your PC. Oct 03, · I recently installed the final version of Microsoft Security Essentials. I was running avast free which I uninstalled before installing security essentials. I also completely uninstalled Windows Defender. I have found a problem with security essentials and Internet Explorer 8 which I am able to repeat % of the time. - Windows Security Essentials or Microsoft Security Essentials is a free antivirus and anti-spyware software for Windows XP i.e SP2 and SP3. It is however not available for Windows XP SP1 or earlier versions of windows.