Windows 7 to improve upon Vista's UAC scheme
 

After years of giving Windows users administrative privileges by default, Microsoft introduced the User Account Control scheme with Windows Vista. In theory, the system brings Windows up to snuff with other operating systems and improves security by requiring users to OK system-level changes. In practice, many users find UAC authorization prompts too numerous and annoying.

All those user complaints haven't fallen on deaf ears. According to a post by Microsoft's Ben Fathi on the Engineering Windows 7 blog, the Windows team is working with users to make Windows 7's UAC implementation more effective and less annoying.
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