SYSTEM MECHANIC PRO (WIN XP,VISTA,WIN 7,WIN 8) Automatic Updates - When you install and activate the software, it will automatically download the newest version to your computer. Compatibility - Works with Windows 7, 8, 8.1 and Windows 10. Unlimited PCs - Installs this tune-up utility on all the PCs in your household Powerful Tools - Fixes errors and crashes; Restores system speed; Cleans up system cluster; Blocks virus and spyware; Frees up trapped RAM & boosts processor speed. Improves your PC performance by defragging hard drive, repairing Windows registry, tweaking CPU & RMA usage, etc. System Defense - Permanently wipes sensitive data; System Shield - Blocks virus and malware; Anti-Spyware - Stops malicious actions and identity theft.