If your computer is not connected to the Internet, you can use the offline installer instead of the web installer to install this update. However, we recommend that you use the web installer to install this update if you are connected to the Internet. The .NET Framework 4.5.1 (Offline Installer) package is larger than the .NET Framework 4.5.1 (Web Installer) package.
The .NET Framework 4.5.1 Language Pack contains localized resources for supported languages. It contains translated error messages and other UI text for languages other than English. If you don't install a language pack, this text is displayed in English. You can install multiple language packs on one computer, each for a different language.
You must download and install the .NET Framework 4.5.1 (Offline Installer) before you install the language packs.
Download informationThe following files are available for download from the Microsoft Download Center:
The .NET Framework 4.5.1 (Offline Installer)
The .NET Framework 4.5.1 Language Packs (Offline Installer)
For more information about how to download Microsoft support files, click the following article number to view the article in the Microsoft Knowledge Base:
What is new in the .NET Framework 4.5.1?The .NET Framework 4.5.1 supports the use of C#, Visual Basic, and F# code. Additionally, the .NET Framework 4.5.1 provides the following language and framework improvements:
- Performance and reliability improvements
- The ability to suspend and resume operations in the ASP.NET page framework
- The ability to compact large object heaps on-demand
- 64-bit Edit and Continue controls
- The ability to trace and sample activities
- Improvements that make SQL connections more resilient
- The ability to manage return values
The .NET Framework Developer Center
The .Net Framework Blog
The .NET Framework 4.5.1 runs side-by-side with the .NET Framework 3.5 Service Pack 1 (SP1) and earlier versions of the .NET Framework. However, the .NET Framework 4.5.1 is an in-place update for the .NET Framework 4 and the .NET Framework 4.5.