Compiler error: Accessibility.IAccessibleis defined in an assembly that is not referenced

Hi,

I'm developing a C# application in VS 2005.

I'm referencing following dlls. Infragistics is a third party dll.

using System;

using System.Windows.Forms;

using System.ComponentModel;

using System.ComponentModel.Design;

using System.Runtime.InteropServices;

using System.Drawing;

using System.Drawing.Text;

using System.Drawing.Design;

using System.Windows.Forms.Design;

using System.Collections;

using System.Diagnostics;

using System.Security.Permissions;

using Infragistics.Shared;

using Infragistics.Win;

using Infragistics.Win.IGControls;

using Infragistics.Win.UltraWinTabs;

// serialization

using System.IO;

using System.Runtime.Serialization;

using System.Runtime.Serialization.Formatters;

using System.Runtime.Serialization.Formatters.Binary;

using System.Runtime.Serialization.Formatters.Soap;

using Infragistics.Shared.Serialization;

using System.ComponentModel.Design.Serialization;

using System.Reflection;

I'm getting following error.

error CS0012: The type 'Accessibility.IAccessible' is defined in an assembly that is not referenced. You must add a reference to assembly 'Accessibility, Version=2.0.0.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a'.

Accessiblity is declared in System.Windows.Forms which I'm referencing in my application.

It is being refernced from C:\WINDOWS\Microsoft.NET\Framework\v2.0.50727\System.Windows.Forms.dll.

And Copy Local was set to TRUE.

Do I need to change any other settings?

Please help me. It is blocking my progress.

 

Thanks,

Sindhu Meka