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一般用户通常没有安装新程序的权限，如果想赋予普通用户以安装权限，有两种方法：
1) 在 MMC 里添加 Group Policy Object Editor, 设置如下： BOTH Computer Configuration & User Configuration -> Administrative Templates -> Windows Components -> Windows Installer, change the “Always install with elevated privileges” to be Enabled.

2) 更改注册表：Set the AlwaysInstallElevated registry value to "1" under the following registry keys: HKEY_CURRENT_USER\Software\Policies\Microsoft\Windows\Installer & HKEY_LOCAL_MACHINE\Software\Policies\Microsoft\Windows\Installer (same change as #1 but done manually with regedit).

两篇参考文章：
http://support.microsoft.com/kb/259459/EN-US/
http://msdn.microsoft.com/library/default.asp?url=/library/en-us/dnlong/html/AccProtVista.asp