C# error when trying to add an inherited component in Toolbox

Question

I am trying to create a component that inherits from a Combox. I created the component by following the steps below, the project is available at: https://dl.dropboxusercontent.com/u/74275347/ComponentesProprios.rar

• No open project >File > New > Project > Class Library (Visual C#) > Name: "Components"
• Delete Class1.Cs
• In the project "Right click" > Add... > Component > Component Class (Visual C# Items) > Name: "Comboboxex"
• In References > Add Reference... > Search for "Forms > Mark System.Windows.Forms > OK
• In the "code" change Componentfor ComboBox > add using System.Windows.Forms; > in public ComboBoxEx() under InitializeComponent(); add DropDownStyle = ComboBoxStyle.DropDownList;
• Save and "build"
• In a Windowsformsapplication project I right click on a tab of "Tollbox" > Choose Items... > in the tab. NET Framework Components > click on Browse.. > I select "C: C# branches Repository Componentssums bin Debug Componentssums.dll"

This is when the message and error "There are no Components in 'C: C# Programming branches Repositorio Componentesproprios Componentesproprios bin Debug Componentesproprios.dll' appears that can be placed on the Toolbox."

Bomboboxex class using System; using System.Collections.Generic; using System.Componentmodel; using System.Diagnostics; using System.Linq; using System.Text; using System.Windows.Forms;

namespace ComponentesProprios
{
    public partial class ComboBoxEx : ComboBox
    {
        public ComboBoxEx()
        {
            DropDownStyle = ComboBoxStyle.DropDownList;
        }

        public ComboBoxEx(IContainer container)
        {
            container.Add(this);
        }
    }
}

Answer 1

According to some answers I saw in Soen the problem may be on itself Visual Studio and there are two things that have to be done to try to solve the problem.

1. Right click on the Toolbox and then click on Reset Toolbox
2. Instead of clicking on Choose items, try to drag the dll inside the Toolbox

Answer 2

Check that the version of . NET that made the components is compatible with the version of the project where you want to use them.

For example, do not create a component in . NET 4.5 and try to use it in an . NET 3.5 application.