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+#Requirements
+
+This library requires .NET 4.5. If you need support for .NET 4.0, you may use [version 1.1.1](https://www.nuget.org/packages/Sendgrid/1.1.1)
+#Installation
+
 To use SendGrid in your C# project, you can either <a href="https://github.com/sendgrid/sendgrid-csharp.git">download the SendGrid C# .NET libraries directly from our Github repository</a> or, if you have the NuGet package manager installed, you can grab them automatically.
 
 ```