Microsoft released final version (RTW) of "Security Essentials," which is an Anti-Virus/Anti-Spyware software for "latest" Windows operating systems. I said "latest", because it is only available for: Windows XP x86 Windows Vista x86 and x64 Windows 7 x86 and x64 Installation was very simple and fast. Once you download MSE from this LINK and run installer, a windows pops out with useful information on what MSE really is. On the second screen you're prompted to validate your copy of Windows. For those of you who are not using genuine versions of Window, installation will fail. Process of validation is very fast and it's finished in a second. Once your copy of Windows is validated you may proceed with installation of Microsoft Security Essentials. Installation shouldn't take long. Once installation completes and you run the MSE for the first time, MSE will update virus definitions and will make initial quick scan of your PC. User interface can't be simpler. To perform a System Scan, you can choose one of the three options, Quick, Full, or Custom (familiar?). First, although quick scan already ran on the initial application startup, I tried to performed a quick scan again to see the speed of it. The Quick scan was very quick on my system. Scan completed on 87948 items in less than 2 minutes, pretty impressive if you ask me. I won't run the full system scan as it would probably take longer to complete as this process scans all of your disks/partitions/files. As for the custom scan, you have an option to choose the drive or destination which you want to scan. Update tab is has only once button to click, guess which. UPDATE!, although MSE should be updated automatically. History tab will shows you All of the detected items, Quarantined items or Allowed items, depends on your selection. Settings tab has all other options that you might need to configure Microsoft Security Essentials, although once you install it, you don't have to touch it, as it will do the job properly. If you still wan't to configure MSE other than default, here's what you can change/configure: Scheduled scan - Here you can select/deselect a scheduled scan of your computer, configure time and type of the scan with two additional options (Check for the latest virus & spyware definitions before running a scheduled scan and Start the scheduled scan only when my computer is on but not in use, although MSE is running in low priority so you shouldn't notice any performance downgrades during the scan. Default Actions - Here you can choose how will MSE react in various situations/alert levels. Real-time protection - Real-time protection alerts you when viruses, spyware, or other potentially unwanted software attempts to install itself or run on your computer. You can select if you want to monitor file and program activity on your computer and if you want to scan all downloaded files and attachments. Excluded files & locations, Excluded file types and Excluded processes - Here you can choose which files, locations, file types or processes would you like to remove from scanning. Useful, if you want to perform faster full scan of your computer. Advanced - Advanced tab gives you the option to scan archive files like .zip or .cab files. You can also choose if you want to scan removable drivers, which isn't enabled by default, but I highly recommend it. You can create a system restore point prior cleaning your computer and give permission to all other users on your PC to view items in the History tab. Microsoft SpyNet - Microsoft SpyNet program is an online community which helps stop the spread of new malicious software infections. You can choose Basic membership (default) or Advanced membership which will send more info to Microsoft about malicious software on your computer, like how the software operates, and how it has impacted your computer. Conclusion: This is the first antivirus application from Microsoft with integrated Anti-Spyware protection. So far I’m really impressed with MSE, because it's small ( setup just under 5MB), fast, stays out of your way and doesn’t hog your resources. Update: Confirmed, MSE won't work if you have 'Checkpoint' software installed on Windows Vista x86. Expect freezes, bad performance etc.