After almost 6 months in Beta, Microsoft Security Essentials 4.0 is ready for download. This is the latest version of Microsoft’s free anti-virus/anti-malware utility and what I use to protect my own PCs.

“Microsoft Security Essentials is a free download from Microsoft that is simple to install, easy to use, and always kept up-to-date so you can be assured your PC is protected by the latest technology,” a description on the Microsoft Security Essentials 4.0 download page notes. “It runs quietly and efficiently in the background so you’re free to use your Windows-based PC the way you want—without interruptions or long computer wait times.”

New features in MSE 4.0 include a streamlined user interface, better performance, and a refined remediation experience for threats that need to be quarantined.

MSE 4.0 runs on Windows XP with SP3, Vista with SP1/SP2, or Windows 7. The technologies behind this application will be bundled with the Windows Defender utility in Windows 8 as well, negating the need for a separate download in the future.

Download Microsoft Security Essentials 4.0.