Why are my server controls grayed out in the Visual Studio Toolbox?

You are using the incorrect version of .NET for your website build.

This example uses Ektron version 9.1 sp1, which uses .NET 4.5.

To fix the graying out of the Toolbox > Server controls, use .NET 4.5 for the website. To do this:

1. Open Visual Studio.
2. Right-click your website. 
3. Click Start Options > Build . 
4. Set Target Framework to .NET Framework 4.5 .