The Microsoft .NET Framework 4 redistributable package installs the .NET Framework runtime and associated files that are required to run and develop applications to target the .NET Framework 4.
Supported Operating System
Windows 7, Windows 7 Service Pack 1, Windows Server 2003 Service Pack 2, Windows Server 2008, Windows Server 2008 R2, Windows Server 2008 R2 SP1, Windows Vista Service Pack 1, Windows XP Service Pack 3
Windows XP SP3, Windows Server 2003 SP2, Windows Vista SP1 or later, Windows Server 2008 (not supported on Server Core Role), Windows 7, Windows Server 2008 R2 (not supported on Server Core Role), Windows 7 SP1, Windows Server 2008 R2 SP1
Supported Architectures: x86, x64, ia64 (some features are not supported on ia64 for example, WPF)
Hardware Requirements:
Recommended Minimum: Pentium 1 GHz or higher with 512 MB RAM or more
Minimum disk space: x86 – 850 MB, x64 – 2 GB
Prerequisites: Windows Installer 3.1 or later, Internet Explorer 5.01 or later