The Microsoft .NET Framework 4.5.1 is a highly compatible, in-place update to the Microsoft .NET Framework 4 and the Microsoft .NET Framework 4.5. The offline package can be used in situations where the web installer cannot be used due to lack of internet connectivity.
Supported Operating System
System Requirements: Windows Vista SP2,Windows 7 SP1, Windows 8, Windows Server 2008 SP2 Windows Server 2008 R2 SP1 and Windows Server 2012
Windows 7 Service Pack 1, Windows 8, Windows Server 2008 R2 SP1, Windows Server 2008 Service Pack 2, Windows Server 2012, Windows Vista Service Pack 2
Hardware Requirements:
1 GHz or faster processor
512 MB of RAM
850 MB of available hard disk space (x86)
2 GB of available hard disk space (x64)